Eight M≥7.0 earthquakes have occurred around Bayan Har block since 2000, resulting huge casualties and countless economic loss. Specifically, four M≥6.0 earthquakes occurred near the western boundary of Bayan Har block from 2008 to 2020. Stress interactions among them are comprehensively investigated by applying ETAS (epidemic-type aftershock sequence) model and calculating dCFS (Coulomb failure stress change). The viscoelastic dCFS induced by proceeding Yutian earthquakes on hypocenters of 2012, 2014 and 2020 Yutian earthquakes are -1.5004×10^-4 , 3.5820×10^-3 and 1.4770×10^-1 MPa, respectively. The background probabilities of 2008, 2012, 2014 and 2020 Yutian earthquakes are 0.87, 0.97, 1.5×10^-3 and 8.7×10^-5, respectively. Combining those two kinds of evidence, we conclude that 2008 and 2012 Yutian earthquakes are more like background earthquakes and 2014 and 2020 Yutian earthquakes are triggered by proceeding Yutian earthquakes.