- Source: 20th Guam Legislature
The 20th Guam Legislature was a meeting of the Guam Legislature. It convened in Hagatna, Guam on January 2, 1989 and ended on January 7, 1991, during the 3rd and 4th years of Joseph F. Ada's 1st Gubernatorial Term.
In the 1988 Guamanian general election, the Democratic Party of Guam won a thirteen-to-eight (13-8) majority of seats in the Guam Legislature.