The electronic structures and binding energy of the defects related to Y3+ dopants in PbWO4 crystals have been investigated by the relativi stic self-consistent discrete variational embedded cluster method.The results show that ［2(Y3+Pb)-VPb”］ is more stable than the other Y3+ r elated defects.Using the transition state method,we find that the transition ene rgy of O2p→Y5d is about 3.9eV.This signifies that Y3+ ions will not res ult in the absorptions at 350nm and 420nm in the PbWO4 crystal.Moreov er,the ef fect on electronic structure in PbWO4 caused by Y dopants is differen t from that caused by La dopants.