This paper reports the geochronological data of detrital zircons from the clastic rocks of Lishan Formation of Early Jurassic in southwestern Fujian, and the aim is ascertaining the composition and source of sediments in Early Jurassic strata revealing the natures of Mesozoic basins South China. The preponderant age compositions reflected by the upper section samples（GMC12）and the lower section samples（GMC22）of Lishan formation are similar, both having one main peak of 1 860 Ma and the other subsidiary peak of 230 Ma. But the age distribution of the lower section samples（GMC22）is relatively simple and the age peaks of 1 860 Ma and 230 Ma are get. The upper section samples（GMC12）show the multi-peak feature and there are multiple subsidiary peaks of about 230 Ma, about 280 Ma, about 410 Ma, about 490 Ma, about 770 Ma and 2 540 Ma except the main peak of 1 860 Ma. The composition of the detrital zircon ages changes from simple to complex from the lower section to the upper section. The upper section has older and complex age compositions than the lower section, suggesting that the provenances might be changed. The Early Jurassic sediment provenances in southwestern Fujian are mainly the Paleoproterozoic and Late Paleozic-early Mesozoic igneous rocks. Based on comparing these detrital zircon ages with those from late Paleozoic and early Mesozoic sediments from different basins around southwestern Fujian, we conclude that Early Jurassic provenances in southwestern Fujian are mainly from north and northeast of the study area. The sediment age compositions within basins from the study area to inland or southern part of South China changed from relatively complex and older to simple and young. From the early to late of Indosinian orogeny, the magmation of South China from the south coastal region to the South China inland but the magmations of South China Eastern coastal, northeast area and northern area were~active.
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