A detailed study of petrology, mineralogy, geochemistry and petrogenesis on the Paleoproterozoic Yanmenguan mafic-ultramafic intrusion in the Hengshan-Wutai-Fuping area is presented here. The intrusion is akin to Alaskan-type or arc-related magmatism in mineral geochemistry, especially in the compositions of spinel, clinopyroxene, and amphibole. The rock geochemistry is also comparative to those of Alaskan-type mafic-ultramafic complexes, as characterized by pronounced Nd (Ta), Zr (Hf), Y and Ti trough in primitive mantle normalized trace element patterns. In trace element discrimination diagrams, the Yanmenguan rocks plot in the field of subduction zone-related magmas, indicating a tectonic setting of continental arc. Therefore, we propose that the magma of the Yanmenguan mafic-ultramafic intrusion originated from lithospheric mantle in a continent marginal arc, and experienced fractional crystallization of olivine and clinopyroxene. This intrusion, together with contemporary granitic and volcanic rocks in this area, signifies an important stage of Paleoproterozoic magmatism developed in continent margin of the Trans-North China Orogen.