Abstract: OBJECTIVE To explore the changes of PCT and CRP concentration in patients with puerperal infection after caesarean section and study the correlation between the two, so as to prevent puerperal infection. METHODS A total of 300 patients with puerperal infection after caesarean section from this hospital during Feb. 2014 to Aug. 2015 were selected as observation group, and another 75 cases of cesarean section without puerperal infection in the same period as control group. The serum PCT, CRP levels of patients in two groups before and after delivery were observed and recorded. The pathogens distribution of observation group was observed as well. The data were analyzed by SPSS 14.0. RESULTS The serum CRP and PCT levels of two group patients before delivery had no significant difference, which began to rise 1d after delivery and the increasing range was bigger and quicker in observation group, and the difference was significant (P<0.05). From the 300 cases of puerpera with infections, a total of 193 strains of pathogens were detected, among which 36 strains of gram-negative bacteria, accounting for 18.65%, and 26 strains of gram-positive bacteria, accounting for 13.47%, and mycoplasma 131 strains, accounting for 67.88%. CONCLUSION The levels of PCT and CRP increase significantly in the body of patients with puerperal infections after caesarean section, and it is hard to recover to normal level, which suggests that the changes of PCT and CRP have some correlation to puerperal infection.