Abstract: An approach for inverting crustal variable density model in wave-number domain from gravity and DSS results by implementing genetic algorithms is investigated. The validity and stability of this method is proved. The exponential density models of crust are inverted from Bouguer gravity anomalies in central Tibetan Plateau, combined with Moho boundaries derived from seism in Yadong-Golmud GGT. The density contrast between crustal surface and mantle is about-0.926g·cm^-3, the average density of crust is 2.750 g·cm^-3 in central Tibetan Plateau.