We have done a comparative analysis of samples selected from 17 Han dynasty bronze mirrors from Shangmashan in Anji, Zhejiang Province and Linzi, Shandong Province, using a combination of stereo, metallographic and scanning electron (with energy dispersive spectrometry) microscopy. The results show that 1) the surfaces of the bronze mirrors from Shangmashan are better preserved (similar to “Heiqigu”, ancient bronzes with dark protective layers like black lacquer), with preferential corrosion of the α-phase in the inner layer; 2) the bronze mirrors from Linzi have heavy surface corrosion, with deposition of cuprous oxide and basic cupric minerals outside and preferential corrosion of the δ-phase inside. Pourbaix diagrams were used in the analysis and discussion of the environments of these two corrosion phenomena. It appears that the preferential types of corrosion seen in the α-phase and the δ-phase in the inner layer of high tin bronze mirrors seen in different environments are related to the different corrosion products outside.