The invention relates to a bacterial cellulose and poly-Beta-hydroxyethyl methacrylate composite material and a preparation method thereof. The bacterial cellulose and poly-Beta-hydroxyethyl methacrylate are adopted as raw materials and the preparation method comprises the steps that a bacterial cellulose film is immersed in a mixed solution of the poly-Beta-hydroxyethyl methacrylate; the film isthan taken out and protected with nitrogen gas pumped and then reacts for six to eight hours under the temperature of 70 DEG C and is immersed in deionized water for 1 to 2 weeks. The bacterial cellulose and poly-Beta-hydroxyethyl methacrylate composite material provided by the invention has good mechanical property and transparency, high rate of water content and better shielding effect of ultraviolet light. In addition, the tensile strength of the composite material can achieve 3.5MPa and the equilibrium moisture content is about 36 to 38 percent and the light transmission rate can be up to75 to 80 percent.