Abstract: At present,the Junggar basin meets with the trans- formation of exploration target and the lithologic reservoir exploration becomes an inevitable trend.In order to carry out the lithologic reservoir exploration perfectly,the pe- troleum accumulation elements of Jurassic lithologic reser- voir and its controlling factors have been discussed.The results show that favorable petroleum accumulation ele- ments are the followings:abundant hydrocarbon source, good storage performance,effective source-reservoir- seal assemblage and great migration and accumulation sys- tem.Two kinds of petroleum accumulation patterns have been summarized,the first is unconformity and faults con- trolled reservoir with far source,and the second is the un- conformity and faults controlled reservoir within source. The controlling factors can be listed as follows:oil-gas distribution is controlled by palaeo-uplift,oil-gas mi- gration and accumulation by unconformity,reservoir scale by reservoir quality,vertical distribution by source-res- ervoir-seal assemblage,and the formation is controlled by broken-slope zone.