The Galinge skarn iron deposit, one of the large skarn deposits in the west of China, is located in the middle of the contact zone between the Qimantag orogen and the Qaidam basin, and possesses abundant potential values. This paper aimed to make specific research on the mineralogy of the Cl-rich amphiboles from the Galinge deposit so as to investigate the association of melt, fluid and minerals. The Cl-rich amphibole belongs to the magnesian hastingsitic subgroup, and its geochemical characteristics are 0.3< Mg/(Mg+Fe²⁺) <0.69; Si <6.25 apfu; and 0.681% < Cl <3.161%. The content of X_Cl shows the positive linear relation with the X_Mg, and the X_K and X_Fe²⁺ show the strong inverse relation with the X_Cl. The linear relation between the cation and the chlorine can be interpreted by the crystal structure consideration of Cl-rich amphiboles. In respect of the substitution between the Cl^- and OH^-, the Cl incorporation is expressed empirically by the function of ln (X_Cl/X_OH)_amp=ln (f_Cl/f_OH)_fluid +A·^[4]Al·Fe²⁺/RT+B/RT, where A and B are constant. Therefore, if all Cl-rich amphiboles are in equilibrium with the coexisting fluid at the same temperature and if each amphibole is in equilibrium with a fluid of relatively constant f_Cl/f_OH, the ln(X_Cl/X_OH)amp versus ^[4]Al·Fe²⁺ should show a linear correlation, and the effect of the cation substitution is contributed by the structure constraints for ^[4]Al and by a chemical constraints for Fe²⁺. The existence of amphibole zones implies that the X_Cl values decrease first and then increase from the core to the edge, since OH is preferentially incorporated relative to Cl. Therefore, when the free fluid phase is gradually consumed as a consequence of continued hydration/chloridisation reactions, the Cl^- content of the fluid should be increased. The crystal/liquid partitioning behavior of the trace elements is controlled by the framework of the lattice, and the volatile concentration in the fluid is also a key factor. The decrease of the Cl concentration in the fluid is attributed to the increase of the REE partition coefficients. Generally, the high saline hydrothermal fluid exsolved from the magma in the early crystallization stage is the dominated reservoir of metals because of the high Cl^- content and low pH value. The Cl^- plays an important role in the transportation of metals. When the ore fluid is reacted with an alkaline carbonate wall rocks, or mixed with meteoric water, the chlorine complex of iron would decompose and precipitate. Meanwhile, the increased pH value makes the f_OH of fluid ascend, which is beneficial for the incorporation of OH into the amphibole.