1940 Idaho Southern Branch Bengals football team

The 1940 Idaho Southern Branch Bengals football team was an American football team that represented the University of Idaho, Southern Branch (later renamed Idaho State University) as an independent during the 1940 college football season. In their sixth and final season under head coach Guy Wicks, the team compiled a 3–5 record and were outscored by their opponents by a total of 185 to 96.

Idaho Southern was ranked at No. 498 (out of 697 college football teams) in the final rankings under the Litkenhous Difference by Score system for 1940.