Ronnie W. Cromer (born December 1, 1947) is an American politician. He has represented South Carolina Senate District 18 (Lexington, Newberry, and Union counties) since 2003. He is a member of the Republican Party.
Cromer served on the Prosperity Town Council for seven years (1973-1980).
Cromer is a Republican member of the South Carolina Senate, representing the 18th District since 2003, when he won a special election against Jim Lander to fill the remainder of the term of André Bauer.
Cromer chairs the Senate Banking and Insurance Committee, and serves on the Senate Finance, and Fish Game and Forestry Committees.
In June 2023, Cromer endorsed Tim Scott in the 2024 United States presidential election.