Cretopiesma suukyiae , new genus and species, is described, based on a unique female specimen in mid-Cretaceous (c. 100 myo) amber from northern Myanmar. Features of C. suukyiae unique for the small Recent family Piesmatidae include a long, protrudent clypeus, a dorsal carina of the head, lack of “jugal” lobes/appendices, widely separated coxae, very large scutellum, and the venation of the corium; some of these are plesiomorphic and shared with Aradidae. C. suukyiae possesses the cuticular areolation and propleural cavities distinctive to Piesmatidae. Phylogenetic analysis of Recent and fossil genera of piesmatids resulted in a cladogram with Cretopiesma as sister group to the remainder of the family. Relationships of this unusual species and of Piesmatidae within Pentatomomorpha are discussed.