Dubei class target ship (AGT) and range supporting vessel is a very little known auxiliary ship of the People's Liberation Army Navy (PLAN), and has received the NATO reporting name Dubei class. Originally built as a SWATH test platform, it was subsequently converted to a target ship by adding radar reflectors and other electronic equipment to simulate various targets in support of anti-ship weaponry development, but is still capable of housing different scientific instruments to perform various research tasks, and thus also acts as general purpose research ship (AGE).
Type 639 is a type of ocean surveillance ship is a type of oceanographic surveillance ship developed by China for its People's Liberation Army Navy (PLAN) to replace earlier Type 595. A single unit of Type 639 with pennant number Bei-diao 992 is currently in service as an oceanographic research ship and five more modified version serving as hydrographic survey ships are designated as Type 639A. Type 639 has received NATO reporting name Kanhai class, 勘海 in Chinese, meaning Surveying Sea.
The Dulaji class are a class of environmental research ships (AGER) currently in service with the People's Liberation Army Navy (PLAN), and the design is also modified for cable layer (YRC) in PLAN service, with both versions have received the same NATO reporting name Dulaji class because they share the same hull. The exact type of this class remain unknown as of 2022, because no official information has been released, despite the ships have already been in service for more than a decade. In addition to the usual task of conducting regular environmental sampling, monitoring/surveillance and research missions, these ships are also tasked with additional task of sewer transfer and treatment from other ships to prevent sewer onboard other ships from overflowing into the sea and thus causing pollution, and thus these ships also act as sewer vessels for vessel sewage discharging.
Dongleng -class reefer ship is a class of naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN), and at least thirteen units were completed and entered service with PLAN from 1960 through 1962. This class can carry between seven hundred to eight hundred tons of frozen cargo.
Beiqi 384 class crane ship is a class of naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type still remains unknown, and only a single unit of this class have been confirmed in active service as of mid-2010s.
Beijun 204 class dredger is a class of little known naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type still remains unknown, and only a single unit of this class have been confirmed in active service as of mid-2010s. In comparison to other dredger in Chinese military service, Beijun 204 class is also capable of performing floating pile driver missions with two piles it is equipped with, one on each side of the ship.
Dongjun 417 class dredger is a class of little known naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type still remains unknown, and only a single unit of this class have been confirmed in active service as of mid-2010s. Dongjun 417 class is a bucket dredger.
Dongjun 433 class dredger is a class of little known naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type still remains unknown, and only a single unit of this class have been confirmed in active service as of mid-2010s. Dongjun 434 is a bucket wheel dredger.
Dongjun 434 class dredger is a class of little known naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type still remains unknown, and only a single unit of this class have been confirmed in active service as of mid-2010s. Dongjun 434 is one of the few Chinese naval ships made by western countries, and it is built by DEMAG.
Nanjun 610 class dredger is a class of little known naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type still remains unknown, and a total of two of this class have been confirmed in active service as of mid-2010s.
Nangong 681 class floating pile driver is a class of little known naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type remains unknown, and only a single unit of this class have been confirmed in active service as of mid-2010s.
The Dumuju class is a class of dispatch boat (YFL) currently in service with the People's Liberation Army Navy (PLAN). The exact type still remains unknown, and it has received NATO reporting name Dumuju class, with only a single unit of this class have been confirmed in active service as of mid-2010s.
Duzhou class dispatch boat (YFL) is a class of naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN), and has received NATO reporting name Duzhou class, with the exact type still remains unknown, and only a single unit of this class have been confirmed in active service as of mid-2010s.
Nanshui 701 class water tanker is a class of little known naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type still remains unknown, and only a single unit of this class have been confirmed in active service as of mid-2010s.
Type 633 heavy-lift ship is a type of little known naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type still remains unknown, and a total of three of this class have been confirmed in active service as of mid-2010s. Type 633 is mainly deployed in rescue and salvage operations.
The Beituo 617 class tug is a little known class of naval auxiliary currently in service with the People's Liberation Army Navy (PLAN). The name of this class is taken from that of the first unit commissioned, with the exact type still remaining unknown; a total of two of this class have been confirmed as being in active service as of the mid-2010s. The Beituo 617 class is a single deck design with a two level superstructure, a platform is atop of the second level.
Beituo 715 class tug is a class of little known naval auxiliary ship currently in service with the People's Liberation Army Navy (PLAN). The name of this class is after the first unit commissioned, with the exact type still remains unknown, and since the commission of the first unit in 1980, a total of seven of this class have been confirmed in active service as of mid-2010s. This class of tug is a single hull and single deck design, with deck covers.
The Longma class is a class of little known diving support vessel (YDT) built in the People's Republic of China (PRC) for the People's Liberation Army Navy (PLAN). The exact domestic Chinese type designation remain unknown, and this class is identified by its NATO reporting name Longma class, or 龙马 in Chinese, meaning "dragon horse". As of mid 2010s, a total of four ships have been identified, and one of them Nan-Jiu (南救) 509 has been retired at the end of 2018.
The Dukou class is a class of little known dispatch boat (YFL) built in the People's Republic of China (PRC) for the People's Liberation Army Navy (PLAN). The exact domestic Chinese type designation remain unknown, and this class is identified by its NATO reporting name Dukou class, or 渡口 in Chinese, meaning Crossing Wharf. The Dukou class in PLAN service is designated by a combination of two Chinese characters followed by a two-digit number. The second Chinese character is Jiao (交), short for Jiao-Tong-Ting (交通艇), meaning dispatch boat (ferry) in Chinese, because these ships are classified as dispatch boats. The first Chinese character denotes which fleet the ship is service with, with East for East Sea Fleet, North for North Sea Fleet, and South for South Sea Fleet. However, the pennant numbers are subject to change due to the change of Chinese naval ships naming convention, or when units are transferred to different fleets. As of mid 2010s, a total of five ships have been identified:
The Yanjiu class is a class of little known survey vessel (AGS) built in the People's Republic of China (PRC) for the People's Liberation Army Navy (PLAN). The exact domestic Chinese type designation remain unknown, and this class is identified by its NATO reporting name Yanjiu class, or 研究 in Chinese, meaning research. The Yanjiu class in PLAN service is designated by a combination of two Chinese characters followed by a three-digit number. The second Chinese character is Ce (测), meaning Survey in Chinese. The first Chinese character denotes which fleet the ship is service with, with East for East Sea Fleet, North for North Sea Fleet, and South for South Sea Fleet. However, the pennant numbers are subject to change due to the change of Chinese naval ships naming convention, or when units are transferred to different fleets. As of mid 2010s, a total of two ships have been identified:
PRC 