Šakiai is a city in Marijampolė County, Lithuania. It lies in the southwestern part of the country, approximately 65 kilometres (40 miles) west of Kaunas.
The city serves as the administrative centre of its surrounding area within Marijampolė County, one of Lithuania's ten counties. Its position west of Kaunas places it within the Sūduva (Suvalkija) ethnographic region, a predominantly agricultural part of the country.