On the basis of study and analysing of layout, contents and composition of muralpaintings in the screen form in caves of the Mogao Grottoes in the period of Tibetandomination at Dunhuang, the present paper has divided these caves into four groups andmade classification and daticg of them, then concluded characteristics and law of devel-opment of the screen paintings of the four groups caves , The paper has also analysed re-lations between the screen paintings and statues in the niches and the special positionthey occupy in the caves and inferred what the main Buddha’sname is. Finally, the pa-per made a research on the history of the screen paintigs and why the form and layout ofthe paintings in caves coutd be popular in the period of Tibetan Domination at Dun-huang. So we can get a glimpse of secular tendency of Buddhist art in caves of that peri-od bv all these.