Purpose Physical function frequently declines after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the influence of disease status and general condition at transplantation on longitudinal functional changes remains unclear.Methods This retrospective study included 135 adult patients with hematological malignancies who underwent their first allo-HSCT and completed physical function assessments before transplantation and at discharge. Handgrip strength and 6-minute walk distance (6MWD) were evaluated. Patients were stratified according to disease status (complete remission [CR] vs. non-CR) and general condition (performance status [PS]).Results Both handgrip strength and 6MWD decreased significantly after transplantation in all groups. No significant differences in functional changes were observed between the CR and non-CR groups. In contrast, patients with poor PS at transplantation tended to show a greater decline in 6MWD than those with good PS. Multiple regression analysis identified PS at transplantation, age, sex, and change in hemoglobin level as significant factors associated with changes in 6MWD.Conclusion Pretransplant PS was associated with a greater posttransplant decline in endurance capacity, regardless of disease status. PS may serve as a practical clinical indicator for identifying patients at higher risk of physical function deterioration and for guiding early targeted rehabilitation interventions.