Abstract: Aiming at the concern about light performance of light guide plate (LGP) and taking light transmittance and haze as optical indices, the effects of molding method, process parameters and product structure on the optical performance of the LGP made from metallocene cycloolefin copolymer (MCOC) were investigated. The results indicated that the light transmittance of injection-compression molded LGP was normally higher than that of the ones molded by other methods. The injection-compression molding method made the LGP the highest value of 93.73 % with a haze lower than other molding methods. With an increase in mold temperature, the haze tended to increase for all of the LGP products, and there was no remarkable change found in melt temperature. The light transmittance of thin-wall LGP was found to be higher than that of the thick wall one. Moreover, the light transmittance of the dot-slot structural LGP was higher than the groove structural one, but its haze was much lower.