By measuring the thermally stimulated current (TSC) spectra at various fields in low-density polyethylene with inorganlc filler (f LDPE) and comparing with those in LDPE, we found that thelr TSC spectra shew slgnificant distinction. in virtue of analysing change of peak current,peak temperature and activation enew with pollng field, it can be depicted that the TSC in f-LDPE specimen comes from dipole relaxation of residual silanol groups on surface of filler, but the injected electrons in very high 6elds, no doubt, are captured in deeper traps, and they can not be released even near 100"C. The filler (kaolin) plays a key role in changing the TSC spectra through deep and interfacial traps existing between the filler and the polymer matrix. Whereas,the TSC spectra of LDPE specimen possess marked characteristics of electron release from traps in amorphous-crystalline or crystalline region.