The invention discloses a method for evaluating the health degree of photovoltaic cell panel set strings. The method comprises a step S101 of collecting PV characteristic curve data of each set string; a step S102 of calculating set string dispersion; a step S103 of calculating set string dispersion speed; a step S104 of calculating set string attenuation rate; and a step S105 of calculating set string attenuation speed. According to the method, the health degree of the photovoltaic cell panel set strings of a whole power station is monitored comprehensively, the monitored data categories are rich, the monitored data volume is large, monitored data have good real-time performance, and users can master quality of the photovoltaic cell panel set strings of the whole power station and follow-up development conditions comprehensively in real time.