In this paper, we give a generalized Cline's formula for the generalized Drazin inverse. Let R be a ring, and let a, b, c, d ∈ R satisfying (ac) 2 = (db)(ac), (db) 2 = (ac)(db); b(ac)a = b(db)a, c(ac)d = c(db)d. Then ac ∈ R d if and only if bd ∈ R d. In this case, (bd) d = b((ac) d) 2 d. We also present generalized Cline's formulas for Drazin and group inverses. Some weaker conditions in a Banach algebra are also investigated. These extend the main results of Cline's formula on g-Drazin inverse of Liao, Chen and Cui (Bull. Malays.). As an application, new common spectral property of bounded linear operators over Banach spaces is obtained