This study develops a slider sensor in which a fiber Bragg grating is considered to be the sensing element and combined with a silicone rubber and a bracket using polymethyl methacrylate, to measure the coefficient of friction (COF) between silicone rubber and a contact object. Further, the relationship between the strain measured by the fiber Bragg grating and COF is theoretically analyzed. The COF is measured based on the mean value and standard deviation of the strain measured by the fiber Bragg grating when the slider is sliding. Experimental results show that the mean strain decreases with the COF, and the maximum sensitivity is -443.7481 με/unit when the COF is 0.34-0.435. Furthermore, the standard deviation of strain increases exponentially with the COF, and the maximum measuring sensitivity is 284.5672 με/unit. The method for measuring the COF can be used in the field of tactile perception with respect to mechanical fingers and has broad application prospects.