The most indium-rich deposits are cassiterite-sulfide deposits or tin-rich sulfide deposits, and these deposits have an intimate relationship with the acidic magmatism. However, it is not clear that the role of tin in indium mineralization. It's also unclear that the geochemical behavior of indium and tin during granite evolution, metamorphism and hydrothermal processes. This article examines the indium behave with tin, copper, lead and zinc in granite, mineralized gneiss and skarn respectively from 5 mining district of Yunnan Province (the Bozhushan granitic pluton and the host enclave, the Nanwenhe gneiss in Dulong deposit), Guangxi Province (the Damingshan deposit in Kunlunguan granite), Hunan Province (granites from the Shizhuyuan and Qitianling mining areas). The results show that : (1) Mica minerals are the main carrier minerals of indium in granite, however, indium is an incompatible element in granitic magma during its magma crystallization, and most indium tends to remain in the melt. The magmatic evolution is a process of indium gradual enrichment, and the geochemical behavior of indium may be similar to tin. (2) Indium and tin contents are positive correlation in ore-forming fluids, which inferred that they have similar geochemical behaviors and migrate together in fluids. Though, it is not clear the migrate mechanism of tin and indium, they are two adjacent elements of the third cycle on the periodic table, they have similar ion-structure and both can form complicated complex. If tin and indium form the multi-core complex or multi-dentate complex in ore-forming fluid, they can move together. Indium contact has a positive relationship with tin in some altered minerals (phengite in Nanwenhe gneissic granite rock, garnet and diopside in skarn of Dulong depoist), showing that indium and tin still have similar geochemical properties during fluid-rock alteration reaction. ( 3 ) Except a small number of independent minerals, indium is mostly found in other minerals. Whether indium gets into other minerals depends on the mineral structure, ion radius and electrovalence. Sn is 6 times coordination and the ionic radius is 0.83 angstrom in cassiterite, while the metal ions are 4-order coordination, with Zn2+ (0.74 angstrom), Cu+ (0. 74 angstrom), Fe2+ (0. 78 angstrom) respectively in sphalerite, chalcopyrite and tetrahedrite. The ion radius is 0. 94 angstrom or 0. 76 angstrom respectively for In3+ of 6 or 4 coordination structures. In the middle-low temperature, cassiterite and sulfide ( such as sphalerite, chalcopyrite and tennite) formed at the same time, In3+ with Cu+ instead of Zn2+ or Fe2+ enter sulfide. (4) Indium enrichment not only has mineral specificity, it may also be affected by the composition of magma minerals. Bainiuchang deposit in Yunnan Province, Shizhuyuan deposit and Furong deposit in Hunan Province are all tin polymetallic deposits, comparing the indium content of the three mineralization-related granites (Bozhushan, Qianlishan and Qitianling), the indium contents of the Bozhushan granite is lower than that of the Qianlishan granite and Qitianling granite, while the Sn/In ratio of the Bozhushan granite is higher than that of the Qianlishan granite and Qitianling granite. It implies that indium mineralized granite was extracted more indium or it has a higher Sn/In ratio. In short, indium mineralization is closely related to tin.