Malmköping is a locality in Flen Municipality, in Södermanland County, Sweden. Malmköping lies at 59 m above sea level. It has 1,992 inhabitants (2023). The nearest city is Eskilstuna, 29 km to the northwest. Among the landmarks around are Gripsholm Castle (31 km), Strängnäs Cathedral (32 km) and Floda Church (22 km).