The present disclosure provides an energy saving controlling method of an inverter air-conditioner, including: a main controlling unit of the inverter air-conditioner receiving settings of an energy consumption and an operating time; according to the set energy consumption and the set operating time, calculating or retrieving operational parameters of the inverter air-conditioner based on that the inverter air-conditioner consumes the set energy consumption in the set operating time; and controlling the inverter air-conditioner to operate according to the calculated or retrieved operational parameters. By receiving the settings of the energy consumption and the operating time from user which can be combined with the target indoor temperature, and calculating or retrieving the corresponding operational parameters of the inverter air-conditioner, the inverter air-conditioner can operate according to the operational parameters, which allows the user to control the energy consumption and the using cost of the inverter air-conditioner directly and accurately.