Abstract The contribution of postseismic relaxation to the induced Coulomb stress and its comparison with that of static Coulomb stress changes imparted by 1997 Mw 7.6 Manyi earthquake were investigated. The results show that standard deviation of combined static and viscoelastic Coulomb stress changes and their means are not larger than 0.005 MPa,which is less than typical triggering value 0.01 MPa, indicating there was no obvious triggering effect on 2001 Kokoxili earthquake caused by static and viscoelastic Coulomb stress imparted by 1997 Manyi earthquake. Stress redistribution due to postseismic relaxation of lower crust or upper mantle didn’t dramatically affect stress environment around the hypocenter of 2001 Kokoxili earthquake. It might be that the dynamic Coulomb stress decaying more slowly than those other two which offered the contribution to triggering the 2001 Kokoxili earthquake.