Unidirectional hybrid laminates based on glass fibers (GF) and high performance polyethylene fibers (PEF) were prepared with a partially polymerized methyl methacrylate (MMA) matrix at room temperature followed by heating at 55°C for the stipulated time (well below the softening point of PEF). The ultimate flexural strength (UFS), flexural modulus (FM) and interlaminar shear strength (ILSS) of the composites were determined and analyzed. An interesting observation of the study was the change in flexural behavior, which was largely dependent on the position of GF and PEF ply/plies in the compression and tension sides. When the ply/plies of PEF were at the tension side, the UFS and FM showed a higher value than that when GF plies were in the tension side of the hybrid composites. The ILSS also follows the same trend regarding the position of the GF and PEF plies. Copyright © 1995 John Wiley & Sons, Ltd.