Water Rats is an Australian TV police procedural broadcast on the Nine Network from 1996 to 2001. The series was based on the work of Sydney Water Police who fight crime around Sydney Harbour and surrounding locales. The show was set on and around Goat Island in Sydney Harbour.

Water Rats premiered on 12 February 1996, and ran for six seasons and 177 episodes. Colin Friels and Catherine McClements were the original stars of the series and were instrumental in the show's early success. They both departed the show in 1999. In later seasons, Steve Bisley, Aaron Pedersen and Dee Smart became the show's main stars.

For the sixth and final season in 2001, the show concentrated more on the cops' personal lives rather than just focusing on the crimes committed. The Nine Network cancelled the show after six seasons. Executive Producer Kris Noble blamed escalating costs for the cancellation. However, the series had been suffering a ratings decline following the departure of Friels and McClements in 1999.

The final episode was broadcast in Australia on 7 August 2001.