Mesozoic volcanic rocks developed in the Da Hinggan Mts., Northeastern China are characterized by highK, highalkali trachytic calcalkaline seri es and ev olu ted from acid to intermediatebasic with the progressive time. Their REE, trace element features and isotopic Sr, Nd compositions distinctly reveal two magma sources,a l ower crust and a relatively undepleted or primary mantle one,indicating that pet rogenesis of the Mesozoic volcanic rocks in the area is ass o ciated with crustmantle interaction resulted from upwelling of deep intraconti nental asthenoli t h.In addition, taking into consideration the migration of volcanic cent er and characteristics of the movement between neighboring continental and oce anic plates in the e ast,it is proposed that there is no direct relationship between Mes ozoic volcanism in the Da Hinggan Mts. and subduction of the oceanic plate.