Geochemical characteristics of sedimentary rocks can indicate palaeoenvironment evolution process. The Jurassic sediments in northern margin of Qaidam Basin recorded significant palaeoenvironmental and palaeoclimatic information of northwest China. Based on the geochemical analysis of sedimentary rocks from the Dameigou standard geological profile in northern margin of Qaidam Basin,palaeoclimate and palaeoenvironment of the Middle to Late Jurassic were reconstructed. The results revealed that: (1)From the Middle to Upper Jurassic,it showed a shallow-water environment with oxic condition,deep lacustrine facies with anoxic condition only appeared in a short time occasionally. In general,the lacustrine water-body in the Jurassic displayed moderate palaeosalinity,but the decrease in precipitation may lead to salinity increase in some intervals. (2)Comprehensive utilization of multiple geochemical parameters,palaeoclimate evolution sequence of the Middle to Late Jurassic in northern margin of Qaidam Basin was established. According to the long-term records,the palaeotemperature and palaeohumidity fluctuation varied within a certain range. From the late Middle Jurassic,the palaeoclimate changed from warm and humid into hot and arid,which triggered the hot and arid palaeoenvironment of the Late Jurassic. The diversified geochemical profile of this study will provide new evidence and materials for the research on the Middle to Late Jurassic hotarid climate event and palaeoclimate correlation in northwest China.