The invention discloses a novel heat accumulating type compressed air energy storage system. On the basis of a heat accumulating type compressed air energy storage system, work procedures of the system are optimized, by the characteristic that a compressor unit and an expansion unit share a heat exchanger, the compressor unit, a heat accumulating system and the expansion unit are coupled together well through a three-way reversing valve, and problems that interstage heat exchangers of the heat accumulating type compressed air energy storage system are arranged repeatedly, system processes are not reasonable, excessive lands are occupied, cost is high, heat energy utilization rate is low, then system running efficiency is reduced and the like are solved. The novel heat accumulating type compressed air energy storage system has the advantages of simple and compact structure, high system efficiency, good heat exchange effect, low manufacturing cost and the like.