The subfamily Sericothripinae Karny (Thysanoptera: Thripidae) is recorded for the first time from the Saudi Arabian fauna. Four species belonging to two genera, Hydatothrips Karny and Neohydatothrips John, are recognized, and H. bahaensis Rasool, sp. n. is described from Al Baha region (southwestern of Saudi Arabia). Host-plant associations are given for the new species and also N. amygdali Minaei, and the male and larvae of N. amygdali are reported for the first time. An illustrated key to the genera and species is provided.