Jászfényszaru is a town in Jász-Nagykun-Szolnok county, in the Northern Great Plain region of central Hungary.

It covers an area of 76.16 km2 (29 sq mi) and has a population of 5567 people (2015).

Jászfényszaru is at the mouth of Zagyva and Galga rivers.

The town has 2 twin-cities: Zakliczyn (Poland) and Bors (Romania).

It has the second largest Samsung factory in Europe after the Slovakian one.