Lubricants are provided which are aluminium or aluminium alloy plate moulding lubricants, and are lubricants which are easily removed after moulding of aluminium or aluminium alloy plate and assembly; also, bonding and welding can be performed while coated with those lubricants, and the bonding and weld strength obtained are the same as if there were no adhering lubricant. Their main constituents are a polyalkylene oxide or derivative thereof and a higher fatty acid salt. It is preferable if they contain 50 to 2 weight % polyalkylene oxide or derivative thereof, and the ratio of higher fatty acid salt and polyalkylene oxide or derivative thereof is within the range 1/12 to 1/4, and further that they contain water. When these lubricants are formed into a 0.2-2.0 g/m<2> solid film on the surface of the aluminium or aluminium alloy plate, this is suitable for moulding processes.