Water polo has been part of the Summer Olympics program since the second games, in 1900. A women's water polo tournament was introduced for the 2000 Summer Olympics. Hungary has been the most successful country in men's tournament, while the United States is the only team to win multiple times at the women's tournament since its introduction. Italy is the first and only country to win both the men's and women's water polo tournaments.
The Slovakia men's national water polo team is the representative for Slovakia in international men's water polo. The governing body is from 2017 Slovak Swimming Federation. It was established in 1993 as the successor state of the Czechoslovakia, so all its results fully belong to it.
The 2012 Men's Water Polo Olympic Qualification Tournament was held at the Kinsman Sports Centre in Edmonton, Alberta, Canada, from 1 to 8 April 2012.
The 2012 Women's Water Polo Olympic Qualification Tournament was held at the Polo Natatorio Bruno Bianchi in Trieste, Italy, from 15 to 22 April 2012.
2014 Men's European Water Polo Championship Qualifiers are series of qualification tournaments to decide the participants of the 2014 Men's European Water Polo Championship, running from 4 April 2013 to 12 April 2014.
The water polo tournaments at the 2016 Summer Olympics in Rio de Janeiro took place from 6 to 20 August at the Maria Lenk Aquatics Centre in Barra da Tijuca. Twenty teams competed in the tournament. Games that ended in ties in elimination rounds were decided by shootouts, as overtime has been abolished since 2013.
Croatia competed at the 2016 Summer Olympics in Rio de Janeiro, Brazil, from 5 to 21 August 2016. This was the nation's seventh consecutive appearance at the Summer Olympics. The Croatian Olympic Committee confirmed a roster of 87 athletes, 68 men and 19 women, to compete across 18 sports at the Games.
2016 Men's European Water Polo Championship Qualifiers are series of qualification tournaments to decide the participants of the 2016 Men's European Water Polo Championship.
The 2016 Men's Water Polo Olympic Qualification Tournament was held in Trieste, Italy, from 3 to 10 April 2016, at the Polo Natatorio "Bruno Bianchi". The top four teams advanced to the Olympics.
The 2016 Women's Water Polo Olympic Qualification Tournament was held at the Groenhovenbad in Gouda, Netherlands, from 21 to 28 March 2016. The top four teams advanced to the Olympics. The mascot of the event was an orange lion in blue clothes called Swimba.
2018 Men's European Water Polo Championship Qualifiers are series of qualification tournaments to decide the participants of the 2018 Men's European Water Polo Championship.
The 2018 Women's European Water Polo Championship was held from 14 to 27 July 2018 in Barcelona, Spain.
Hungary competed at the 2020 Summer Olympics in Tokyo. Originally scheduled to take place from 24 July to 9 August 2020, the Games were postponed to 23 July to 8 August 2021, because of the COVID-19 pandemic. Hungarian athletes have appeared in every edition of the Summer Olympic Games, except for two occasions. Hungary was not invited to the 1920 Summer Olympics in Antwerp, because of its role in the first World War, and was also part of the Soviet boycott, when Los Angeles hosted the 1984 Summer Olympics.
The 2020 Men's European Water Polo Championship was the 34th edition of the major European water polo tournament for national teams. It was held at the Danube Arena in Budapest, Hungary, from 14 to 26 January 2020.
The 2020 Men's European Water Polo Championship Qualifiers are a series of tournaments aimed to establish the participants of the 2020 Men's European Water Polo Championship. The matches were played from 11 to 13 October 2019.
The 2020 Women's European Water Polo Championship Qualifiers are a series of qualification tournaments aimed to establish the participants of the 2020 Women's European Water Polo Championship. The matches were contested in April and October 2019.
The 2020 Women's European Water Polo Championship was the 18th edition of the major European water polo tournament for national teams. It was held at the Danube Arena in Budapest, Hungary, from 12 to 25 January 2020.
This article presents the national team appearances in the men's Olympic water polo tournament since the inaugural official edition in 1900.
Hungary – winners of the 2016 Women's European Water Polo Championship 
Netherlands – runners-up of the 2016 Women's European Water Polo Championship
Italy – 3rd place of the 2016 Women's European Water Polo Championship
Spain – 4th place of the 2016 Women's European Water Polo Championship
Greece – 5th place of the 2016 Women's European Water Polo Championship
Russia – 6th place of the 2016 Women's European Water Polo Championship
