Maplewood is a city in Ramsey County, Minnesota, United States. The population was 42,088 at the 2020 census. Maplewood is ten minutes' drive from downtown Saint Paul. It stretches along the northern and eastern borders of Saint Paul. Maplewood is home to the corporate headquarters and main campus of 3M Corporation. The city is also home to the Maplewood Mall and St. John's Hospital.