New fusulinid collections from the Baoshan Block in southwest China necessitate paleobiogeographic reevaluation of the Mid-Permian fusulinids in this region. From Xiaoxinzhai Section in the southern Baoshan Block, 32 fusulinid species of nine genera are described and illustrated. Among them, Eopolydiexodina parva is a new species, and elements of Neoschwagerinidae and Verbeekinidae are confirmed. The studied fusulinids are ascendingly grouped into three biozones: the Schwagerina yunnanensis Range Zone, Eopolydiexodina Abundance Zone, and Sumatrina annae Range Zone. The lower two could be assigned in age to the Murgabian and the uppermost one to the Midian. Midian fusulinids are for the first time reported from the Baoshan Block. In terms of fusulinid paleobiogeography, these three assemblages should belong to the western Tethyan Province A because of the presence of Eopolydiexodina and characteristic Tethyan genera, e.g., Verbeekina, Sumatrina, and Pseudodoliolina. Moreover, these assemblages may occupy a comparatively high latitudinal region within Tethyan Realm, judging from the overall low diversity.