thumb|260px|A false scale propaganda engraving of 17th century Torshälla from [[Erik Dahlberg's Suecia Antiqua et Hodierna ]]
Torshälla () is a locality situated in Eskilstuna Municipality, Södermanland County, Sweden with 7,612 inhabitants in 2010.
Torshälla was during the Middle Ages the dominant trading town in Rekarne, the northwestern part of Södermanland County, which roughly corresponds to present day Eskilstuna Municipality. After neighbouring Eskilstuna was granted town rights in 1659, Torshälla lost in relative importance due to the rapid growth of industry and trade in Eskilstuna, the building of a canal bypassing the rapids in Torshälla, and the great fire which devastated Torshälla in 1798.
Industrial era
The development of Torshälla during the 19th and 20th centuries was greatly influenced by the foundation of an ironworks on the lands of Nyby manor house on the western outskirts of Torshälla. The Nyby Bruk ironworks was founded in 1829 by the silversmith and industrialist Adolf Zethelius. The mill village of Nyby Bruk grew up around the ironworks, forming a symbiotic relationship with the neighbouring town.
Several small tool making and mechanical industries were established in Torshälla during the mid- to late 19th century, using the available water power around the river; Johan Termaenius' mechanical works (1846), F O Nyström's tin vessel factory (1854), Ali Andersson's Torshälla saw blade factory (1881) and Holmens' foundry & mechanical works (1888).
In 1895 the Northern Södermanland Railway was connected to Nyby Bruk, bypassing Torshälla town centre. Passenger traffic on the line was discontinued in 1933 after which the tracks were exclusively used for freight to Nyby.
During the years between 1900 and 1940, Torshälla experienced dwindling population numbers with recession hitting the local manufacturing industry hard.