Abstract: Objective To investigate the changes of C reactive protein(CRP) and erythrocyte sedimentation rate(ESR) in elderly patients after lumbar surgery and their clinical significance. Methods A total of 176 elderly patients undergoing lumbar surgery in our hospital from May,2016 to June,2017 were selected. Fifteen patients,got postoperative infection,which were included as infection group; 161 patients without postoperative infection were included as the control group.The levels of CRP and ESR in 1,3,5,7,14 and 21 d in serum before and after operation were detected. Results The CRP level of the infection group and the control group of patients before lumbar operation were (9.5±2.6) mg/L and (9.8±1.9) mg/L,there was no statistically significant difference(t=0.565,P=0.573);The CRP level after lumbar operation of two groups were (121.80±3.2) mg/L and (35.0±4.3) mg/L,the difference was statistically significant.The ESR level of the infection group and the control group of patients before lumbar operation were (16.3±3.2) mm/h and (16.6±2.9) mm/h,there was no statistically significant difference; The ESR level after lumbar operation of two groups were (75.4±6.8) mm/h and (36.0±4.6) mm/h,the difference was statistically significant(t=21.947,P<0.001).The average level of CRP3 and ESR in the infection group after lumbar surgery in 21d was significantly higher than that in the control group,which showed an increasing trend with time,and reached the peak value at 3d after the operation,and then decreased gradually.CRP and ESR peak of the infection group of patients were significantly higher than that of control group. Conclusion The elderly patients undergoing lumbar surgery after treatment was detected in the CRP level and ESR level can more effectively judge the postoperative infection,so that early detection and early treatment.