The 191st Massachusetts General Court was the meeting of the legislative branch of the state government of Massachusetts, composed of the Senate and the House of Representatives. It convened in Boston at the Massachusetts State House, on January 2, 2019, and ended on January 6, 2021, during the fifth and sixth years of the governorship of Charlie Baker. Senate and House districts were drawn based on the 2010 Census.

The Massachusetts Senate is the upper house of the Massachusetts General Court, the bicameral state legislature of the Commonwealth of Massachusetts. The Senate comprises 40 elected members from 40 single-member senatorial districts in the state. All but one of the districts are named for the counties in which they are located. Senators serve two-year terms, without term limits. The Senate convenes in the Massachusetts State House in Boston, the state capital.