The latest TV anime season of Gintama ended in march 2016 but Weekly Shounen Jump has already announced that Gintama will get a new season that will air on TV Tokyo. For more information see the TV anime’s official webpage: http://www.tv-tokyo.co.jp/anime/gintama/index2.html.
The series is based on a manga written by Hideaki Soraichi that started in 2003, that’s currently on its 65th volume. The manga entered its final arc in July 2016. The first TV anime season aired in 2006.