The invention relates to an indoor air quality evaluation system and method. The evaluation system comprises an acquisition module, a judgment module, a calculation module and a signal transmission module, wherein the acquisition module is used for acquiring a plurality of measured values of air quality parameters of a living room in current season and sending the measured values to the judgment module; the judgment module is used for judging whether the measured values are in separate-corresponding current-season preset standard ranges or not, obtaining a plurality of judgment results and sending the judgment results to the calculation module; the calculation module is used for carrying out calculation according to the judgment results to obtain an air quality comprehensive evaluation value and controlling the signal transmission module to send a corresponding preset air quality grade to a terminal device for displaying through the air quality comprehensive evaluation value. According to the system and the method, through carrying out acquisition and judgment on the air quality parameters of the current season and obtaining an evaluation value to reflect air quality of the living room through a judgment result, an effective data support is provided for comprehensive control on the air quality of the living room.