Abstract: A method and apparatus for coupling the drive shaft of an integrally molded modular screw conveyor is disclosed. A non-circular elongated drive shaft includes a non-circular axially extending aperture for receiving a first end of a coupling member having a corresponding size and shape such that rotation with respect to the shaft and coupling member is not possible. In addition, both the shaft and the coupling member define aligned recesses for receiving a locking pin so as to also prevent axially movement between the two. An integrally formed screw conveyor module includes an axially extending aperture with a size and cross-sectional shape for slideably receiving the drive shaft such that rotation is prevented between the drive shaft and the module. The locking pin is held in position by sliding the module over the locking pin when it is in place within the shaft and coupling member.