Alsip is a village in Cook County, Illinois, United States. The population was 19,725 at the 2000 census. It is a suburb of Chicago. Alsip was settled in the 1830s by German and Dutch farmers. The village is named after Frank Alsip, the owner of a brickyard that opened there in 1885. The village began to grow after the Tri-State Tollway was built there after World War II.