Purpose: For classical Hodgkin lymphoma (cHL), programmed death-l (PD-1) is a well-recognized attractive target. This multicenter, single-arm, phase II study evaluated the efficacy and safety of camrelizumab, a humanized high-affinity IgG4 mAb against PD-1, in Chinese patients with relapsed or refractory cHL. Patients and Methods: Patients who had failed to achieve a remission or experienced progression after autologous stem cell transplantation or had received at least two lines of systemic chemotherapies were given camrelizumab 200 mg every 2 weeks. The primary endpoint was objective response rate per independent review committee (IRC) assessment. This study is registered with ClinicalTrials.gov (NCT03155425). Results: Between June 9, 2017 and September 18, 2017, 75 patients were enrolled and treated. At a median follow-up of 12.9 months, 57 of 75 (76.0%; 95% CI, 64.7-85.1) patients achieved an IRC-assessed objective response, including 21 (28.0%) and 36 (48.0%) patients who had complete and partial remission, respectively. Median duration of response was not reached (range, 0.0(+) - 12.8(+) months). Treatment-related adverse events (AE) occurred in all patients. The most common ones included cutaneous reactive capillary endothelial proliferation (97.3%, 73/75) and pyrexia (42.7%, 32/75). Grade 3 or 4 treatment-related AEs occurred in 20 patients (26.7%); the most common AE was decreased white blood cell count (4.0%, 3/75). There were no grade 5 treatment-related AEs. Conclusions: Camrelizumab demonstrated a high response rate, durable response and controllable safety in Chinese patients with relapsed or refractory cHL, becoming a new safe and effective treatment option in this setting.