?? [Abstract]? Objective? To explore the effects of reciprocal behavior on perceived stress among nurses during the second pregnancy. Methods? From January to March 2018, we selected clinical nurses during the second pregnancy at five Class Ⅲ hospitals in Zhejiang as subjects by convenience sampling. The questionnaire survey was carried out with the employee reciprocal behavior questionnaire and the Chinese version Perceived Stress Scale (CPSS) to explore the correlation between them. A total of 500 questionnaires were sent out and 482 valid of them were collected with 96.40% for the valid recovery rate. Results? Among 482 nurses during the second pregnancy, the scores of reciprocal behavior and perceived stress were (42.35±8.65) and (38.38±7.58) respectively. Perceived stress of 33.61% of nurses during the second pregnancy was at a normal level. Reciprocal behavior had a negative correlation with the perceived stress (r=-0.411,P＜ 0.01). Hierarchical regression analysis showed that reciprocal behavior was the influencing factor of the perceived stress of nurses during the second pregnancy. Conclusions? Reciprocal behavior has the influence on perceived stress among nurses during the second pregnancy which points out that managers and individuals can improve reciprocal behavior so as to reduce the stress of nurses during the second pregnancy.