Hazelwood is a city in St. Louis County, Missouri, within Greater St. Louis. It is a second-ring northern suburb of St. Louis. Based on the 2020 United States census, the city had a total population of 25,485. It is located north of St. Louis-Lambert International Airport and is situated on Interstates 270 and 170, as well as the much-traveled Lindbergh Boulevard and Highway 370.