The surface-bonded fiber Bragg grating (FBG) sensor consists of three parts: fiber, middle layer, and matrix. By analyzing the ratio of the elastic modulus of the colloid to the optical fiber, the influences of the elastic modulus, Poisson''s ratio, length and other factors of the colloid on the average strain transfer rate from the matrix to the optical fiber are explored. Compared with the average strain transfer rate without considering the elastic modulus ratio. Experimental results show that when considering the elastic modulus ratio, the average strain transfer rate increases with the increase of elastic modulus and length of colloid, decreases with the increase of thickness and Poisson''s ratio of colloid, and first increases and then decreases with the increase of colloid width. The research results are more in line with the actual application.