Judson Linsley Gressitt (16 June 1914 – 26 April 1982) was an American entomologist and naturalist who worked in Japan and China.

Through his cousin E. Gorton Linsley, he became interested in insects and the outdoors as Boy Scouts where they were influenced by Brighton C. Cain.

He worked towards the end of the war with the US Medical Research Unit in Guam, Philippines, and Japan.

In the 1950s he returned to work in Southeast Asia and took part in an expedition to study Metasequoia glyptostroboides, a living fossil in Sichuan.

[6][8] The species Paramelomys gressitti; the leaf-beetle genera Gressittella and Gressittana; and the horsefly genus Gressittia are named after him.