This is a multi-center, open-label, phase 2 study evaluating the humanized anti-PD-1 antibody JS001, as a monotherapy in patients with locally advanced or metastatic bladder urothelial carcinoma who have failed in routine systemic treatment.The implementation of study meet the GCP.370 patients will be enrolled in the study to evaluate the safety and efficacy of JS001.Patients are injected with JS001 with 3mg/kg every 2 weeks until disease progresses or unacceptable toxicity occurs.Response assessment is conducted by every 8 weeks in first year, every 12 weeks in second year and every 16 weeks in third year and beyond.