We conducted a retrospective study to evaluate the clinical impact of an early recovery of posttransplant absolute lymphocyte count (ALC) on the outcome of frontline autologous stem cell transplantation (ASCT) for diffuse large B-cell lymphoma (DLBCL). We reviewed 65 DLBCL patients who underwent frontline ASCT after primary chemotherapy based on cyclophosphamide, doxorubicin, vincristine, and prednisone. A receiver operating characteristic analysis was performed to determine the optimal cut point (0.4 × 10 /L) for an ALC at 15 days after ASCT (ALC-15). Both event-free survival and overall survival rates of the higher-ALC-15 group were significantly better than those of the lower-ALC-15 group (event-free survival, P = .008; overall survival, P = .013). The infused CD34 cell count was significantly associated with the recovery of ALC-15 (>0.4 × 10 /L) after ASCT (P = .028). A multivariate analysis confirmed that a higher infused CD34 cell dose (>5.0 × 10  cells/kg) was an independent factor affecting an early recovery of ALC after ASCT (odds ratio, 4.145; 95% confidence interval, 1.106-15.528; P = .035). In conclusion, an early recovery of ALC after ASCT can be regarded as a good prognostic marker in patients with DLBCL who have undergone frontline ASCT. We found that the infused CD34 cell dose for ASCT was associated with the recovery of ALC.