The Humboldt Park riot began in Chicago, resulting in three deaths, three cars in the Humboldt Park lagoon, and increased tension between the Chicago Police Department and the Puerto Rican community.

The Humboldt Park riot was the second major conflict between Puerto Ricans in Chicago and the Chicago Police Department. The riot began on June 4, 1977, and lasted a day and a half. Following the shooting deaths of two Puerto Rican men, locals battled Chicago police officers in Humboldt Park and in the streets surrounding. The riot led the community to hold the Division Street Puerto Rican Day Parade, which started in 1978.

Humboldt Park is an 207-acre (84 ha) urban park located at 1400 North Sacramento Avenue in West Town, on the West Side of Chicago, Illinois. To its west is the neighborhood named after it, also called Humboldt Park. It opened in 1877, and is one of the largest parks on the West Side. The park's designers include William Le Baron Jenney, and Jens Jensen.