Abstract: At present, public cultural service lies in a dilemma, on the one hand, it is in short of supply; on the other hand, it is in short of demands. Under the background of "Internet +", we should reform the traditional supply mechanism which is government-oriented, and establish new supply mechanism which is public-oriented. Beginning with collecting, and recognizing social public demands, through collecting service information, evaluation selection, offering service products and accepting opinion feedback, the realization of public cultural service supply and demand docking can be effectively guaranteed. To establish new supply mechanism for it, we should vigorously implement "Internet +" cultural service supply, positively promote system innovatin, strengthen multi-cultural governance, realize multi accuracy of public cultural service and reshape the organizational system for supply.