A mass balance unit having an integrated secondary unit for an internal combustion engine of a motor vehicle has a mass balance housing in which at least one mass balance shaft is rotatably journaled and has a unit housing in which at least one drive shaft of the secondary unit is rotatably journaled. The mass balance housing is made in one piece such that the mass balance housing has at least one bearing section which surrounds a bearing opening peripherally in one piece in which the mass balance shaft is rotatably journaled. The unit housing is also made in one piece with at least one base section, with a wall section and with a bearing section such that the bearing section of the unit housing surrounds a bearing opening peripherally in one piece in which the drive shaft is rotatably journaled. The drive shaft is operably connected to the balance shaft drivewise. The base section of the unit housing is releasably fastened to a lower side of the mass balance housing. The wall section of the unit housing is arranged at an end face of the mass balance housing.