Gibson Southern High School is a public high school located in Fort Branch, Indiana.

Gibson Southern High School received the Indiana Four Star School Award for seven consecutive years.^{[when?][5][6]}

In 1974, Gibson Southern was originally a member of the Pocket Athletic Conference (PAC). In 1980, the school left the PAC to form the Big 8 Conference with 7 former Southern Indiana Athletic Conference schools, some of which were also once members of the PAC. In 1994, Gibson Southern left the Big 8 to rejoin the PAC.^{[citation needed]} In 2020 the Pocket Athletic Conference expanded with Boonville, Mount Vernon, Princeton and Washington joining Forest Park, Gibson Southern, Heritage Hills, North Posey, Pike Central, Southridge, South Spencer, Tecumseh, and Tell City to make it a 13-team conference.^{[citation needed]}

The school won state championships in softball in 2003, 2005 in class AA and 2015 in AAA, splitting back to back appearances (2014 and 2015) with Leo, and as a result played in class AAAA in the sport from 2016 to 2021.^[7]

In 2021, the football team won their first state championship in school (and Gibson County) history, defeating Indianapolis Brebeuf.^[8]

In 2024, the girls basketball team won their first state title in school history, defeating Norwell. This comes 22 years after finishing runner up in 2002 to Fort Wayne Bishop Luers. As a result of this win, coupled with back-to-back appearances at semi-state, the Lady Titans with now compete in AAAA in girl's basketball for the next two years, provided they do not continue to make deep runs into the tournament, like the softball team did.

• List of high schools in Indiana