Fish bone of silver carp was used as raw material, and calcium content and free amino acid content in solution were used to evaluate the result of fish bones softening. The effects of sub-critical water temperature, treated time, acetic acid concentration, and the solid-liquid ratio on fish bones softening were investigated. Further, the functional properties of fish surimi including treated fish bone were evaluate. The result showed the optimum condition to soften the fish bones included 124 ℃ of sub-critical water temperature, 1.5 h of treated time, 0.9 mol/L of acetic acid concentration, and 1:25 of the solid-liquid ratio. In this condition, the calcium content in per gram fish bone is102.50 mg, and the free amino acid in per gram fish bone is 16.01 mg. Compared with the control, fish surimi containing treated fish bone showed higher water holding capacity, similar gel strength and lower whiteness.