The rapid solidification process of liquid Ag-Cu alloy at different solute concentrations are simulated by molecular dynamics method. The microstructure evolution characteristic of Ag-Cu alloy is analyzed by two-body distribution function, Honeycutt-Andersen bond type index and extended cluster type index method (CTIM). The results show that the main bond type of Ag-Cu quick setting glass alloy is 1551, and the local quintic symmetry are obvious. The main atomic configuration is icosahedral clusters, in which the regular icosahedral cluster (12 12/1551) is dominant. The highest heritable fraction f of Ag-Cu corresponds to the transition temperature of reduced glass, which proves that Ag60Cu40 has the best amorphous forming ability.