BACKGROUND: Autologous peripheral blood hematopoietic stem cell transplantation has been widely used in clinic because of its wide age range, fewer complications and low cost. The reconstitution of hematopoietic function after transplantation mainly depends on the quantity and quality of hematopoietic stem cells. Based on the clinical practice, this paper analyzes various factors affecting the collection of peripheral blood hematopoietic stem cells, and calculates the appropriate blood routine standards. It is of great significance to improve the success rate of peripheral blood hematopoietic stem cell collection and autologous transplantation. OBJECTIVE: To analyze the influence of related factors on the number of CD34+ cells during the mobilization and collection of peripheral blood hematopoietic stem cells of patients with hematological tumors. METHODS: A retrospective analysis of the effects of various factors on the number of CD34+ cells collected during the mobilization and collection of peripheral blood hematopoietic stem cells of 36 patients in Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences was performed from June 2018 to June 2020, including age, gender, body surface area, disease type, various cell levels on the day of collection, number of chemotherapy before collection, and disease before collection factors such as status, presence or absence of bone marrow involvement at the first diagnosis. RESULTS AND CONCLUSION: (1) The number of CD34+ cells was related to the number of leukocytes, the absolute value of monocytes, the proportion of monocytes, and the proportion of lymphocytes on the day of collection, and the difference was statistically significant (all P < 0.05). Further analysis of the above four indicators found that the absolute value of monocytes on the day of collection had the highest predictive value for the number of CD34+ cells, followed by the proportion of lymphocytes, leukocytes, and monocytes. (2) Single factor analysis found that age, disease type, mobilization plan, the number of chemotherapy before collection and the presence or absence of bone marrow invasion at the initial diagnosis had no effect on the final collection success rate, and the difference was not statistically significant (all P > 0.05), while gender, disease status before mobilization, body surface area and the final collection success rate were related, and the differences were all statistically significant (all P < 0.05). (3) Results concluded that after mobilization, the blood routine monitoring is used to determine the collection time of peripheral blood hematopoietic stem cells, which mainly monitor the number of leukocytes, the absolute value of monocytes, the proportion of monocytes, and the proportion of lymphocytes. The absolute value of monocytes is the highest predictive value. The cutoff is 1.345×109 /L. When the subject is male, pre-collection disease state is complete remission or partial remission, and body surface area is large, the final collection success rate is high. [ABSTRACT FROM AUTHOR]