The invention provides an OCA optical cement for a mobile phone glass screen protector. The OCA optical cement is prepared by reaction between the following substances by mass percent: 50-90% of aliphatic polyurethane acrylate, 1-20% of isobornyl methacrylate, 1-20% of 2-ethylhexyl acrylate, 1-20% of hydroxypropyl methacrylate and 0.1-10% of an initiator. The components are sequentially added into a stirred tank by mass percent, uniform mixing and stirring are performed under a dark condition, the mixture is naturally left to stand for defoaming to prepare a glue, after that, a PET release film is coated with the glue by use of a scraper or a coater, and UV curing is performed after attachment of the PET release film. The OCA optical cement has the beneficial effects that the light transmittance is high, the adhesive property, the water resistance and the anti-aging performance are excellent, the stripping performance is favorable, coating production is easy, the 100% curing environmental protection effect is good and the price is low.