| Event | Location | Date | Number killed | Description |
|---|
| 2025 North Codorus Township shooting | North Codorus Township | September 17, 2025 | 4 | Five police officers were shot, three fatally, while serving a court order at a farm house. [1] |
| UPMC Memorial Hospital shooting | Shiloh | February 22, 2025 | 2 | A man shot and killed a police officer and injured six others before being fatally shot by police at UPMC Memorial Hospital. [2] |
| Attempted assassination of Donald Trump in Pennsylvania | Meridian | July 13, 2024 | 2 | Thomas Matthew Crooks shot and killed an audience member and wounding 3 others at a rally near Butler, Pennsylvania. [3] |
| 2022 Philadelphia shooting | Philadelphia | June 5, 2022 | 3 | Two men get into a shootout which killed and injured multiple bystanders. [4] |
| Pittsburgh synagogue shooting | Pittsburgh | October 27, 2018 | 11 | Single gunman attacked a religious congregation. Arrested. |
| Melcoft shooting | Melcroft | January 28, 2018 | 5 | Single gunman attacked a car wash. |
| Eaton Township Weis Markets shooting | Eaton Township | June 8, 2017 | 4 | Single gunman attacked a supermarket. |
| 2016 Wilkinsburg shooting | Wilkinsburg | March 9, 2016 | 6 | Two gunmen attacked an outdoor party. |
| 2014 Montgomery County shootings | Three towns in Montgomery County | December 15, 2014 | 7 | A single gunman attacked his wife's family in several locations. |
| 2014 Pennsylvania State Police barracks attack | Blooming Grove Township | September 12, 2014 | 1 | Eric Frein attacked a Pennsylvania State Police barracks. |
| Ross Township Municipal Building shooting | Saylorsburg | August 5, 2013 | 3 | A single gunman attacked the town council. |
| 2009 Collier Township shooting | Collier Township | August 4, 2009 | 4 | Social loner attacked a gym. |
| 2009 shooting of Pittsburgh police officers | Pittsburgh | April 4, 2009 | 3 | Man attacked policemen responding to a domestic violence call. |
| West Nickel Mines School shooting | Bart Township | October 2, 2006 | 7 | Man attacked an Amish schoolhouse. |
| Lex Street Massacre | Philadelphia | December 28, 2000 | 7 | 3 suspects shot 10 people inside a crackhouse in West Philadelphia. |
| Richard Baumhammers' killing spree | 3 locations in western Pennsylvania | April 28, 2000 | 5 | Racially-motivated murder spree. |
| 2000 Wilkinsburg shooting | Wilkinsburg | March 1, 2000 | 3 | Single gunman kills three people. |
| 1998 Parker Middle School dance shooting | Edinboro | April 24, 1998 | 1 | Teenaged shooter killed a teacher. |
| Murder of Mario Riccobene | Philadelphia | January 28, 1993 | 1 | Mob hit of a turncoat. |
| Springfield Mall shooting | Springfield | October 30, 1985 | 3 | Female killer was later found mentally ill. |
| Moser family shooting | Evansburg | March 31, 1985 | 3 | Single gunman kills his ex-wife and 2 daughters. The killer was executed. |
| 1982 Wilkes-Barre shootings | Wilkes-Barre and Jenkins Township | September 25, 1982 | 13 | Killing spree by a prison guard. |
| Murder of Charles DeVetsco | Harrisburg | October 13, 1980 | 1 | Victim was kidnapped and killed. The killer was executed. |
| Babes in the Wood murders (Pine Grove Furnace) | Unclear | c. November 24, 1934 | 5 | Two shot, three suffocated. |
| Kelayres massacre | Kelayres | November 5, 1934 | 5 | A political parade was attacked by a Republican family. |
| Enoch Brown school massacre | Near present-day Greencastle | July 26, 1764 | 10 | Native American attack. Both gunfire and tomahawks were used. |
