The invention provides a system and a method for averaging load of a backup automatic switch in an alternating current and soft direct current hybrid power supply area. The system comprises a 10-kilovolt alternating current bus bridge which comprises a negative direct current bus bridge and a positive direct current bus bridge, an interconnection electric reactor which is connected with the 10-kilovolt alternating current bus bridge and an interconnection electric reactor which is connected with the interconnection electric reactor. When a transformer B1 in the alternating current transmission and distribution power grid area trips, the load is averaged through an interconnection direct current switch QFP 1 and an interconnection direct current switch QFP 2; or when a transformer B3 in the soft direct current transmission and distribution power grid area trips, the load is averaged through interconnection switches FDL which are arranged between a 10-kilovolt and 1-megabyte bus and a 10-kilovolt and 2-megabyte bus. According to the system and the method for averaging load of the backup automatic switch in the alternating current and soft direct current hybrid power supply area, serious overload and destruction of insulation of the transformers in the alternating current transmission and distribution electric grid power supply area are avoided.