Senator Brennan may refer to:
Bill Brennan (Nebraska politician) (1922–1979), Nebraska State Senate Evie Brennan (fl. 2020s), Wyoming State Senate James B. Brennan (1926–1999), Wisconsin State Senate John A. Brennan Jr. (born 1945), Massachusetts State Senate James Henry Brennan (1888–1949), Massachusetts State Senate Michael F. Brennan (born 1953), Maine State Senate Vincent M. Brennan (1890–1959), Michigan State Senate William C. Brennan (1918–2000), New York State Senate