Based on the relativistic multiconfiguration DiracFock theory, the level energies and level degeneration of ions from Au48+ to Au52+have been calculated using the Generalpurpose Relativistic Atomic Structure Progra m with quantum electrodynamics effect and Breit correction. The partition functi on of each ion is derived using statistical thermodynamics. The equilibrium dist ribution of Au48+to Au52+in Au plasma is obtained from the theory of simultaneous reactions.