Abstract: The Lujiang-Zongyang area in Anhui Province is located in the fault-depression zone of Lower Reaches of Yangtze River.A series of A-type granitoids with various autoliths formed by intensive magmatic activities and frequent crust-mantle interaction during J3-K1 are exposed in this area. Chemically, the A-type granitoids are rich in alkalies, REE and LILE (e.g., Rb, Th and K), but poor in HFSE (e.g., Nb, Ta, Ti and Zr), Sr and P, and have higher ratios of 104×Ga to Al. In contrast, the autoliths are poor in SiO2 and alkalies, but rich in Cr, Co, Sc, V, Zr, and have higher ratios of Eu to Eu*. The autoliths and their host rocks have similar (87Sr/86Sr)i values (0.7053 ~ 0.7089) and εNd (t ) values (-2.2 ~ -8.66). These data support the formation of these A-type granitoids through slight crustal material contamination combined with intensive fractional crystallization of basaltic magma derived from an enriched lithospheric mantle. Lithologies of the A-type granitoids include quartz syenitic porphyry, syenite porphyry, pyroxene monzonite and alkali feldspar granite, and constitute a part of the post-collisional metaluminous mafic-felsic igneous suites. The distribution of all analyzed samples in a small area near the boundary of A1 and A2 on the plots of Nb-Y-Ce、Nb-Y-3Ga and Rb/Nb-Y/Nb for subgroup discrimination of A-type granitoids is consistent with their formation at the end of post-collisional magmatic activity in a setting of lithospheric extension. Therefore, their occurrence marks the end of the post-collisional tectonic setting.