Jill Katherine Underly is an American educator and school system administrator. She is the Superintendent of Public Instruction of the U.S. state of Wisconsin, elected in the 2021 Spring general election.

The superintendent of public instruction, sometimes referred to as the state superintendent of schools, is a constitutional officer within the executive branch of the Wisconsin state government, and acts as the executive head of the Department of Public Instruction. Twenty-eight individuals have held the office since statehood. The incumbent is Jill Underly.