Background <p>The success of hematopoietic stem cell transplantation (HSCT) relies significantly on the effective mobilization and collection of hematopoietic stem cells. However, various factors can lead to failure in hematopoietic stem cell mobilization in some patients, including age, type of malignancy, chemotherapy regimens (such as fludarabine, Melphalan, and Lenalidomide), radiotherapy, bone marrow cellularity, and comorbidities. This study investigates the impact of Diabetes Mellitus type 2 on hematopoietic stem cell mobilization outcomes in patients undergoing autologous transplantation.</p> Materials and Methods <p>We conducted a retrospective analysis of 43 patients, comparing mobilization efficiency, engraftment times, and blood product transfusion requirements between diabetic and non-diabetic cohorts. Mobilization was achieved using granulocyte colony-stimulating factor (G-CSF), with the specific dosing regimen and timing of apheresis detailed in the methods section.</p> Results <p>Our findings indicate that diabetic patients exhibited significantly lower CD34 + cell counts and required more engraftment time than their non-diabetic counterparts (<i>P</i> &lt; 0.05). Additionally, diabetic patients had higher rates of blood product transfusions post-transplantation.</p> Conclusion <p>Our findings have shed light on the impact of Diabetes Mellitus type 2 on Hematopoietic Stem Cells mobilization and autologous transplantation, providing crucial insights for the hematopoietic stem cell transplantation field. It is crucial to recognize that diabetes can significantly affect the outcomes of hematopoietic stem cell transplantation. Factors such as poor stem cell mobilization, prolonged engraftment times, and increased need for blood product transfusions underscore the importance of considering diabetes in HSCT candidates.</p>