Michigan's 1st Senate district is one of 38 districts in the Michigan Senate. It has been represented by Democrat Erika Geiss since 2023, succeeding fellow Democrat Stephanie Chang.
District 1 encompasses part of Wayne County.
District 1, as dictated by the 2011 Apportionment Plan, covered parts of Wayne County along the Canadian border, including much of Detroit as well as River Rouge, Ecorse, Wyandotte, Riverview, Trenton, Woodhaven, Gibraltar, Grosse Ile, and parts of Brownstown.
The district was split three ways among Michigan's 12th, 13th, and 14th congressional districts. It overlapped with the 1st, 2nd, 4th, 6th, 14th, and 23rd districts of the Michigan House of Representatives.