The invention relates to a blast-capacity-variable energy-saving type central air-conditioning system. The blast-capacity-variable energy-saving type central air-conditioning system comprises a main air feeder, air feeding pipes, at least two blast-capacity-variable air feeders, a temperature sensor, a frequency converter and a controller. The controller is connected with the temperature sensor, the frequency converter and the blast-capacity-variable air feeders. The frequency converter is connected with the main air feeder. The main air feeder is connected with the blast-capacity-variable air feeders through the air feeding pipes. Compared with the prior art, the blast-capacity-variable energy-saving type central air-conditioning system has the advantages of being good in flexibility, saving energy, reducing emission, being high in reliability and the like.