Zhuozi Mountain area is situated in the west northern margin of Ordos Basin where well preserved sedimentary records of Ordovician. Based on an analysis of the testing result of 16 clastic rock samples, this paper systemically discuss the geochemical charateristics and its geological significance. Chemical classification of the Wulalike Formation clasolite indicates that the analyzed sediments are unstable litharenite. The sandstones are characterized by moderate SiO2 contents (he sandstones are characterized by moderate SiO2 contents ( 68. 58%~72. 97% ) and K2O/Na2O ratio ( generally 2.2~12.9)and moderate tFe2O3 + MgO contents (2.6%~7.21%) . The REE patterns are characterized by LREE enrichment, flat HREE，and poor negative Eu-and Ce-anomalies. CIA index ( generally 66~75) suggest that these sediments were derived from source rocks with moderate chemical weathering. And Zr /Sc and Th /Sc ratios illustrate that all sediments have undergone moderate degree of weathering and no significant sediment recycling. Various diagrams for sedimentary provenance using major and trace elements show all the sediments studied were derived predominantly from felsic sedimentary rocks source. Sediments were demonstrated to have come mainly from the south-west areas as indicated by restored paleocurrent directions. Geochemical data for these rocks suggest continental island arc and active continental margin settings. Together with regional geological evidence，the provenance of Wulalike Formation could be mainly the North Qilian orogenic belt and the Alxa Block.