This study reports the new discovery of relatively abundant foraminiferal faunas from the upper Serpukhovian-lowermost Bashkirian? of the Ghaleh Formation in the Shahreza region of the Sanandaj-Sirjan Zone, Iran. Four successive assemblages spanning the upper Serpukhovian-lowermost Bashkirian? are proposed: (1) Assemblage with and ; (2) Assemblage with ; (3) Assemblage with and spp., (4) Assemblage with ex gr. . The newly discovered foraminiferal assemblages of the Sanandaj-Sirjan Zone have some species in common with assemblages of the Russian Platform, Donets Basin, Urals, and Western Europe. aff. , and , and a new species sp. nov. are described. The microfacies analysis of the Ghaleh Formation limestones suggests a moderate to high-energy shallow marine warm environment, more likely of the inner ramp.