A pump body assembly, a compressor and an air conditioner are provided. The pump body assembly has a crankshaft, a main bearing, and a cylinder body. The crankshaft has a main shaft part and an eccentric part connected with the main shaft part. The main bearing has a hub part. The main shaft part extends through a through hole in the hub part. A first oil guide groove is formed in the hole wall of the through hole. A sliding vane slot and a center hole are formed in the cylinder body. The crankshaft extends through the center hole. The main bearing is located at the one side of the cylinder body. The crankshaft and the main bearing are in uniform contact with oil films at all positions. The abnormal wear of the main shaft part of the crankshaft can be reduced, and the service life of the compressor can be prolonged.