Objective:To analyze the clinical characteristics of monkeypox patients.Methods:The clinical data and laboratory findings of 4 patients with monkeypox patients diagnosed at Yiwu Central Hospital in July 2023 were analyzed. Herpes fluid and skin tissue samples were collected, the viruses were isolation and cultured in African green monkey kidney cells (Vero) and identified with whole gene sequencing.Results:All four patients were male, aged 24-35 years. All patients had male-to-male behavior within 21 days before onset of the disease. Among them, one patient has AIDS and one patient has syphilis. Four patients presented with perineal skin lesions with itching, and 3 patients were found to have enlarged lymph nodes upon admission. Laboratory testing: lymphocyte abnormality (4.57×10 9/L) in 1 case; increased procalcitonin (0.25 ng/mL) in 1 case; elevated IL-10 levels ( 7.11 ng/L and 9.42 ng/L) in 2 cases; increased IL-6 (66 ng/L) and IL-4 (3.24 ng/L) in 1 case, respectively. One case had abnormal myocardial zymogram with a elevated lactate dehydrogenase level of 313 U/L. The monkeypox virus was isolated from lesion tissue and herpes fluid, and the whole gene sequencing identified it as the B. 1.3 subtype of the IIb evolutionary branch, exhibiting typical pathological effects on Vero cells. Conclusion:The clinical manifestations of the 4 monkeypox patients confirmed in Zhejiang province are mild, patients had a definitive history of male-to-male sexual behavior and the virus strains belong to the B. 1.3 lineage of the IIb evolutionary branch.