The invention discloses a phase change heat storage type air condition cooling reservoir which is composed of an air condition cooling reservoir, a phase change heat storage unit and a phase change material. The phase change heat storage unit has the characteristics of being good in sealing performance, long in service life, convenient to transport and the like, the heat storage unit containing the phase material is placed in the air condition cooling reservoir, the total volume of the phase change heat storage unit can not exceed 25% of rating water storage volume of the reservoir, the heat storage unit in the air condition cooling reservoir is placed in a staggering arrangement mode, the phase change temperature of the phase change material is 26 DEG C to 28 DEG C, and the usage quantity of the phase change material is calculated. When the water temperature of the air condition cooling reservoir reaches to the melting temperature of the phase change material, the large latent heat of the phase change of the phase change material is utilized to absorb heat, and the effects of storing air condition condensation heat and relieving water temperature rise speeds of the reservoir can be effectively achieved; and when the phase change heat storage type air condition cooling reservoir is applied to a new-built air condition cooling reservoir, the new-built scale can be reduced, and on the premise of the same air condition condensation heat, the construction cost can be saved.