Palaeolatitude study can provide quantitative constraints in paleogeographic reconstruction for latitudinal drift of the block during the geological time. This study reappraised the Mesozoic evolution history of the Qiangtang Block, through reevaluating the published paleomagnetic data. The results show that the Qiangtang Block has been in the northern hemisphere subtropical high pressure zone during the Middle to Late Triassic, and collided with its northern tectonic unit. It reached a latitude of 214°N in the Middle Jurassic, with continuous northward drift to 318°N in the Late Jurassic. The magnitude of this drift reached 1154±223km（△λ=10.4°±2.1°）during the Jurassic period. The block had kept a relatively stable paleolatitude during Cretaceous. Combined this tectonic drift history with other geological evidences, such as paleoclimate, tectonic and paleogeography evidences, we believe that the period of the Xiali Formation in the Middle Late Jurassic has had high potential in potash formation.