A phylogenetic study based on 25 species of Phasgonophorinae (Hymenoptera: Chalcididae) and 36 characters was carried out for ensuring the generic placement of three new species from Saudi Arabia. As a result of this study, the genera Trigonura Sichel, 1866, Bactrochalcis Kieffer, 1912, Centrochalcis Cameron, 1913, Centrochalcidia Gahan & Fagan, 1923, Chalcidellia Girault, 1924, Urochalcis Nikol'skaya, 1952, Trigonurella Boucek, 1988, and Muhabbetella Koçak & Kemal, 2008 are synonymized with Phasgonophora Westwood, 1832. This genus is recorded in Saudi Arabia for the first time, represented here by P. rubens (Klug), and newly described species P. baiocchii Soliman & Gul, sp. nov., P. granulis Delvare, sp. nov., and P. magnanii Gadallah & Gul, sp. nov. An illustrated key to species of the Arabian Peninsula is provided. The relevant specimens were mostly reared from buprestid species infesting Acacia sp. and Dodonaea viscosa in Al-Baha, Asir and Riyadh regions, Saudi Arabia.