Objective To investigate the fatigue properties of bone cement specimens prepared with different monomer storing temperatures and polymerization environment temperatures; to find out the combination of the storing temperature of bone cement monomer and the mixing temperature of bone cement. Methods Bone cement monomer was stored under 21 ℃ or 4 ℃ environment. They were mixed with the powder under partial vacuum at room temperature of 21 ℃ for 1 minute, followed by 3 minutes' rest. The cement was then injected into metal molds with different temperatures of 21 ℃ or 50 ℃. Finally, the polymerized cement specimens were removed from the molds for mechanical tests. The bone cement specimens were divided into four groups. Group 1(control group): monomer temperature 21 ℃, metal mold temperature 21 ℃. Group 2: monomer 21 ℃, mold 50 ℃. Group 3: monomer 4 ℃, mold 21 ℃. Group 4: monomer 4 ℃, mold 50 ℃. Each group consisted of 21 specimens. All specimens were soaked in 37 ℃ water bath, and were tested with MTS mechanical test machine. Completely reversed tension-compression cycling loading was applied. Testing strength exerted was 15 MPa and the frequency was 2 Hz. This strength was approximately 3.5 times of the force that cement received in vivo. The cycles to failure was recorded. Specimens that failed in less than 5000 cycles were excluded. Comparisons of cycles to failure among different groups were performed using independent sample t tests. Results The cycles to failure of the control group(group 1) were lower compared with those of group 2, 3 and 4. The differences were all statistically significant(P≤0.001). Conclusion 1) The combination of monomer temperature of 21 ℃ and metal mold (polymerization environment) temperature of 21 ℃ produced the worst bone cement specimens in terms of their fatigue property. 2) The fatigue property was obviously improved when the monomer and the mold temperatures differed by 20 ℃ to 30 ℃.