A double low homozygous two-type sterile line ZY-2AB, its near-isogenie temporary maimainer line ZY-4, and the full sterile line ZY-3 derived fi'om the cross of ZY-2A with ZY-4, were developed to breed three-line dominant (MS hybrid in Brassica napus. Three yeats data showed that the ratios of sterile and frtile plants fit the expected 1:1 ratio in ZY-2AB, and the 1:0 ratio in ZY-3, respeetively. Some double low super hybrid combinations were screened out when the full sterile line ZY-3 was used as female par-ent, among which the combination 01Z24 increased 36.88 pereem more yield than eomrol and the combi-nation 98Z131 has been passed through the Siehuan Provincial Regional Test and registered in Siehuan Province. Two years data showed that the agronomic performance of the two-line hybrids derived from crosses of ZY-2A with re.storer lines versus that of the three-line hybrids produced by ZY-3 was not dirffe-ent for any of the nine most important agronomic characteristics, re.vealing that near-isogenie line of ho-mozygous two-type line was used as temporary maimainer could effectively avoid the disadvantage of three-way cross hybrid in breeding three-line dominant GMS hybrid.