Abstract: Flexural properties of recycled concrete beams were investigated experimentally. The results show that the deflections of recycled concrete beams decrease with increasing tension reinforcement ratio and compressive strength of recycled concrete, and that the measured deflection was larger than calculated deflection by 10% according to the code for design of ordinary concrete structures. Based on theory of ordinary concrete structures, the three coefficients in the stiffness formula were obtained by experiment and a calculating method for the deflection of recycled concrete beams was proposed. The calculated results of mid-span deflection, using the proposed formula, were close to other available test results.