In this research, the fauna of parasitoid wasps (Hymenoptera) was studied in 14 forest regions in Mazandaran province (northern Iran) during 2010-2016. The sampled areas were: Fin Forest Park in Chalus, Dohezar and Sehezar Forests in Tonekabon, Mirza-Kochak-Khan Forest Park in Amol, Dalkhani Forest in Ramsar, Lajim Forest in Sari, Shahid Zare Forest Park in Sari, Khoshroudpey Forest in Galogah, Palang-Darreh in Shirgah, Urim Forest in Savadkooh, Telar Forest Park in Qaemshahr, Asal-Mahalleh in Ramsar, Javarem Forest Park in Zirab, Pahneh-Kola Village in Sari, and Seyed Abusaleh Village in Qaemshahr. In total, 85 parasitoid species within 67 genera and eight families, Braconidae (23 species, 15 genera), Chalcididae (two species, two genera), Chrysididae (four species, three genera), Encyrtidae (six species, six genera), Eulophidae (two species, two genera), Ichneumonidae (41 species, 33 genera), Mymaridae (single species) and Pteromalidae (six species, five genera) were collected and identified. Seven species, Aleiodes pallidicornis (Herrich-Schäffer, 1838), Apanteles parasitellae (Bouché 1834) (Braconidae), Cryptus moschator (Fabricius, 1787), Gelis karakurti (Rossikov, 1904) (Ichneumonidae), Mokrzeckia menzeli Subba Rao, 1981, Solenura ania (Walker, 1846), Solenura nigra (Walker, 1872) (Pteromalidae) are new records for the fauna of Iran.