Background: Immune checkpoint inhibitors (ICIs) showed strong activity and tolerable toxicity in those patients with relapsed or refractory classical Hodgkin lymphoma. However, there was limited data on the long-term survival outcome of those patients after remission due to ICIs treatment. Methods: The data was collected from 4 pivotal phase 2 clinical trials: AK105-201 (penpulimab, NCT03722147), BGB-A317 (tislelizumab, NCT03209973), SHR-1210 (camrelizumab, NCT03155425), GLS-010 (zimberelimab, NCT03655483). The key inclusion criteria included age ≥18 years, relapsed or refractory classical Hodgkin lymphoma, lines of prior chemotherapy ≥ 2, treated with ICIs monotherapy, achieving complete remission (CR) or partial remission (PR). The progression-free survival (PFS) and overall survival (OS) were estimated from the time of registration. Results: Among 324 screened patients, 260 patients (140 with CR, 120 with PR) were enrolled. The median age was 32 years with a male/female ratio of 1.3:1. The median lines of prior chemotherapy was 3 (range, 2-11). Additionally, 184 patients had refractory disease, and 54 patients received autologous stem cell transplantation (n = 45) or brentuximab vedotin (n = 9). With a median follow-up period of 31.1 months, 116 (44.6%) patients underwent disease progression and 18 (6.9%) patients died. The 3-year PFS and OS rates of 55.1% and 89.7% for all patients, respectively. Compared with those with CR, patients with PR had inferior survival outcome (3-year PFS, 29.5% vs. 72.3%, P< 0.001; 3-year OS, 81.5% vs. 94.4%, P = 0.017). In terms of duration of treatment, the 3-year PFS and OS rates were 28.6% and 71.6%, and 74.5% and 98.5% for patients with duration of treatment < 24 and > 24 month, respectively (P values were both < 0.001). Among patients with CR, longer duration of treatment (> 24 month) remained positive impact on the survival outcome (3-year PFS, 81.3% vs. 47.1%, P< 0.001; 3-year OS, 98.1% vs. 82.9%, P< 0.001). Conclusions: Deeper remission and longer duration and led to favorable survival outcome for patients with relapsed or refractory classical Hodgkin lymphoma who achieved remission during ICIs treatment.