Josvainiai (formerly Polish: Jaswojnie, Russian: Ясвойни, Ясвойне) is a small town in Kėdainiai district, central Lithuania.

The town comprises the Catholic All Saints Church, a gymnasium, a post office, a public library, a stud farm, and a culture house.

Historians believe that there was a medieval castle in Josvainiai, attacked many times by the Teutonic Knights.

[1] On July 19, 2006, the town was granted a renewed coat of arms by a presidential decree.

During World War II, 282 Jews were murdered in a mass execution: 86 men, 110 women, and 86 children.