The invention relates to an intelligent air-cooling frequency conversion energy-saving method and an intelligent air-cooling frequency conversion energy-saving system for a transformer. The intelligent air-cooling frequency conversion energy-saving system comprises a detection feedback unit, a programmable logic controller, a working instruction unit, an operating unit, a frequency converter, a remote control unit, a power supply unit and cooler groups. The method and the system can commonly control the number of operating cooler groups and a rotation speed of a fan according to top-layer oil temperature, winding temperature and a load current of the transformer. The top-layer oil temperature and the winding temperature of the transformer serve as frequency modulating and controlling parameters of the frequency converter, and the rotation speed of coolers and engaging and removing of the cooler groups are controlled by taking variation of the load current into consideration. The intelligent air-cooling frequency conversion energy-saving method and the intelligent air-cooling frequency conversion energy-saving system for the transformer can effectively avoid the problem of wasting resources due to facts that an air-cooling frequency conversion energy-saving system and an air-cooling frequency conversion energy-saving method for a transformer in the prior art are poor in flexibility, single in operation mode, low in control precision, large in noise, poor in cooling effect since accurate tracking control is not performed according to variation of the oil temperature and the winding temperature of the transformer, and can not be economically applied to various kinds of complicated occasions and circumstances or achieve economical operation of the coolers.