Lilius Bratton Rainey (July 27, 1876 – September 27, 1959) was a U.S. Representative from Alabama.

Rainey attended the common schools and moved to Fort Payne, Alabama.

He was admitted to the bar in the latter year and commenced practice in Gadsden, Alabama.

Rainey was elected as a Democrat to the Sixty-sixth Congress to fill the vacancy caused by the death of John L. Burnett.

He was a trustee of the state department of archives and history, Montgomery, Alabama.