Objective:To investigate the collection efficiency of peripheral blood hematopoietic stem cells and explore its influencing factors.Method:The parameters of the collection process, blood routine indexes and the number of MNC and CD 34+ cells of the product were detected by Fresenius blood cell separator, Mindray blood cell analyzer and BD flow cytometer. A retrospective analysis was performed on 72 patients who underwent autologous peripheral blood hematopoietic stem cell transplantation in Southwest Hospital of Army Medical University from January 2013 to January 2021, including the correlation among gender, age, blood routine indexes, collection circulation volume and MNC and CD 34+ cell count in these cases, and influence of various factors on collection efficiency of peripheral blood stem cells. The correlation among gender, age, blood routine indexes, collection circulation volume and MNC and CD 34+ cell count in 72 cases of autologous transplantation patients, and influence of various factors on collection efficiency of peripheral blood stem cells were analyzed retrospectively. Results:There were no significant differences in collecting efficiency of peripheral blood stem cells among patients with different age, sex and disease type ( P>0.05). The collected MNC count of all patients was positively correlated with the collection cycle count ( r = 0.33, P<0.001) and WBC count after mobilization ( r = 0.41, P<0.001). The number of CD 34+ cells collected was positively correlated with MNC count after mobilization ( r = 0.38, P<0.001) and the amount of white membrane collected ( r = 0.48, P<0.001). Logistic multivariate regression analysis showed that MNC count after mobilization: P<0.001, 95% CI 0.07(0.05 - 0.09), collection cycle amount [ P<0.001, 95% CI 0.00(0.00 - 0.00)] and postharvest total amount [ P<0.001, 95% CI 0.07(0.05 - 0.10)] were the influencing factors of the collected MNC number. Meanwhile, these factorswere also the influencing factors of the collected CD 34+ number (MNC count after mobilization: P<0.001, 95% CI 0.09(0.04 - 0.14); collection cycle amount: P = 0.003, 95% CI 0.00(0.00 - 0.00); postharvest total amount: P = 0.005, 95% CI 0.08(0.03 - 0.14)). Conclusions:The collection efficiency of peripheral blood stem cells varies greatly among individuals. The more MNC counts after mobilization, the more peripheral blood stem cells could be collected. In order to obtain high collection efficiency, it is necessary to adjust the parameters of peripheral blood MNC before collection, and pay attention to the collection circulation quantity, postharvest total amount and white membrane volume.