Helanshan complex, situated in the western margin of the North China Craton, consists mainly of khondlite series and deformed granitoids (orthogneisses). The former is composed dominently of sillimanite-garnet gneiss, garnet two-feldspar gneiss, leptineite and a bit of marble and granulite, the later consists mainly of biotite plagioclase gneiss, garnet granite, porphyritic: granite and gneissic diorite. By using the zircon SHRIMP U-Pb dating, the authors have been obtained some results for granitoids in this area. The biotite feldspar gneiss and garnet granite formed respectivelly 2053±58Ma and 2047±42Ma, respectively,porphyritic granite and gneissic diorite intruded at 1955Ma and 1920Ma respectively. A lot of geochronology data indicate that a Late-Paleoproterozoic granite zone distributes in the northern margin of the North China Craton. The Late-Paleoproterozoic granitoids formed in three stages, the granitoids of the first stage formed early than 2.0Ca, second stage occurred in 2.0～1.87Ca, the granitoids in third stage intruded at 1.85～1.80Ca. The Late-Paleoproterozoic granitoids in the Helanshan area formed mainly at first and second stage. In the north margin of the North China Craton, Late-Paleoproterozioc granite magmatism accompanied usually by regional metamorphism in time.%位于华北克拉通西缘的贺兰山杂岩主要由孔兹岩系和变形花岗岩(正片麻岩)所组成,前者主要由夕线石榴片麻岩、石榴二长片麻岩、变粒岩和少量的大理岩及麻粒岩所组成,后者主要包括黑云斜长片麻岩、石榴子石花岗岩、斑状花岗岩和片麻状变质闪长岩.本文报道了该区变形花岗岩的锆石SHRIMP U-Pb定年结果.黑云二长片麻岩和石榴子石花岗岩分别形成于2053±58Ma和2047±42Ma,斑状花岗岩和片麻状闪长岩分别在1955Ma和1920Ma侵位.大量的年代学资料表明,在华北克拉通北缘存在一条古元古代晚期的花岗杂岩带,该带中的花岗杂岩主要形成于三个阶段,第一阶段大于2.0Ga,第二阶段主要出现在2.0～1.87Ga期间,第三阶段的花岗杂岩在1.85～1.80Ga期间侵位.年代学研究还表明,古元古代晚期的花岗岩浆作用常常与变质事件紧密相关.
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