Doctor Doctor (also known outside of Australasia as The Heart Guy) is an Australian television drama created by Tony McNamara, Ian Collie and Alan Harris, which premiered on the Nine Network on 14 September 2016, lasting five seasons, concluding on 23 June 2021. The cast includes Rodger Corser, Nicole da Silva, Ryan Johnson, Tina Bursill, Hayley McElhinney and Steve Bisley, and follows the story of Hugh Knight, a rising heart surgeon who is gifted, charming and infallible. He is a hedonist who, due to his sheer talent, believes he can live outside the rules. His "work hard, play harder" philosophy eventually comes to 'bite' him. The series was originally produced by Essential Media & Entertainment and Easy Tiger Productions in association with Screen NSW. Andy Ryan and Jo Rooney served as executive producers.

Doctor Doctor has been positively received throughout its run and has also achieved success outside of Australia in countries such as New Zealand, United States, United Kingdom and Sweden. A ratings success for Nine Network, the series has occasionally been the highest-rated drama on Australian television, peaking at 854,000 during its first season. The series finale was watched by 516,000 viewers. It has been nominated for several awards, including 15 Logie Awards and three AACTA Awards.