Mariestad Municipality (Mariestads kommun) is a municipality in Västra Götaland County in western Sweden. Its seat is located in the city of Mariestad.

The present municipality was formed in 1971, when the City of Mariestad was amalgamated with four surrounding rural municipalities.

Mariestad Municipality is situated on Lake Vänern and is visited by many tourists in summer. The largest fresh water archipelago in Sweden lies within the municipality. Torsö and Brommö are the two largest islands. North of the city, in Sjötorp, Göta Canal meets Lake Vänern.

The largest employers are Electrolux home products and Katrinefors bruk, a part of Metsä Tissue AB. SCA Packaging AB, RM Perfo AB and Jede AB are other notable companies in Mariestad. Within the IT industry Telia Partner AB and WM-data Infra Solutions AB are the two biggest employers. Just south of Mariestad, in Lugnås, you find Nimbus Produktion AB who manufactures Nimbus boats.

This is a demographic table based on Mariestad Municipality's electoral districts in the 2022 Swedish general election sourced from SVT's election platform, in turn taken from SCB official statistics.^[3]

In total there were 24,698 residents, including 19,407 Swedish citizens of voting age.^[3] 47.4% voted for the left coalition and 51.5% for the right coalition. Indicators are in percentage points except population totals and income.