The invention relates to an automatic assembling equipment and assembling method of an automobile wire harness connector. The equipment comprises a rack, a transfer device, a shell feed device, a sealing ring assembling device, a holding block assembling device, a locating buckle assembling device and a discharge device, wherein the transfer device, the shell feed device, the sealing ring assembling device, the holding block assembling device, the locating buckle assembling device and the discharge device are mounted on the rack. The transfer device is arranged in the middle of the rack. The shell feed device, the sealing ring assembling device, the holding block assembling device, the locating buckle assembling device and the discharge device are arranged around the transfer device by a circle in a radial shape. In the machining direction, the shell feed device, the sealing ring assembling device, the holding block assembling device, the locating buckle assembling device and the discharge device are sequentially arranged. Jigs are arranged to contain shells, stability of the shells in the transfer process is kept better, and the structures of the jigs are simple. Inner opening blocks are arranged to open sealing rings, the equipment is more suitable for moving the sealing ring and is more suitable for subsequent assembling, and the assembling success rate is high.