Södermanland Regiment (Swedish: Södermanlands regemente), designation I 10, was a Swedish Army infantry regiment that operated 1634–1942 and 1957–1963. The unit was based in the Strängnäs Garrison in Strängnäs, Södermanland, Sweden. In 1963 the regiment was transferred to the Swedish Armoured Troops under the name of Södermanland Regiment (P 10).