St. Mary's High School is a private, Roman Catholic high school in Storm Lake, Iowa.

It is located in the Roman Catholic Diocese of Sioux City.

[1] Located three blocks from the waterfront of Storm Lake, the school offers a quality, faith-based education.

[2] The Panthers compete in the Twin Lakes Conference in the following sports:[3] The Panthers also combine their sports and compete with Storm Lake Public High School for Wrestling, Cross-Country, and Football at the high school level.

Storm Lake High School competes in the 3A division of Iowa Athletics.