⁃ Over 18 years old, male or female;

⁃ Stage III or stage IV melanoma that has been definitively diagnosed by pathology and/or cytology and has failed at least second-line standard therapy (including chemotherapy, immunotherapy, and targeted therapy for those with genetic mutations) (progression to unresectable or metastatic melanoma within 6 months after the end of adjuvant therapy or during adjuvant therapy, This adjuvant therapy can be considered as advanced first-line therapy) for patients with unresectable or metastatic melanoma;

⁃ The overall percentage of subjects with mucosal melanoma will not exceed 22%;

⁃ Eastern Oncology Consortium (ECOG) physical condition score ECOG 0 \

• 1;

⁃ The expected survival time is more than 3 months;

⁃ At least 4 weeks after completion of previous antitumor therapy (including chemotherapeutic/radiotherapy, targeted therapy, immunotherapy) (at least 2 weeks after completion of previous bone radiotherapy, at least 6 weeks after withdrawal of chemotherapy using nitrosourea and mitomycin), and have recovered from adverse reactions of previous treatment (≤ grade 1 or baseline, except hair loss), and 4 weeks after surgery for major surgery;

⁃ At least one measurable target lesion was present according to RECIST 1.1 criteria. There are lesions suitable for intratumoral injection. Measurable tumor lesions were defined as longest diameter ≥10 mm and scanning thickness less than 5.0 mm. For lymph node lesions, short diameter ≥15 mm.

⁃ Asymptomatic central nervous system metastases, or treated asymptomatic brain metastases, must be examined by computed tomography (CT) or magnetic resonance imaging (MRI) for no disease progression, stable for at least 3 months, and without steroid medication for at least 4 weeks;

⁃ No severe dysfunction of major organs; Laboratory tests meet the following criteria:

• WBC≥3.0×109 / L, ANC≥2.0×109 / L (no correction by granulocyte colony stimulating factor \[G-CSF\] or granulocyte macrophage colony stimulating factor \[GM-CSF\] within 14 days prior to screening), PLT≥100×109 /L (do not receive platelet infusion or thrombopoietin \[TPO\], thrombopoietin (TPO) receptor agonist or interleukin-11 \[IL-11\] within 14 days before screening), Hb≥90 g/L (do not receive blood transfusion or erythropoietin \[EPO\] correction within 14 days before screening);

∙ Blood BUN and blood creatinine within the range of 1.5 times the upper limit of normal value;

∙ TBIL≤ 1.5 times the upper limit of normal (total bilirubin \<2×ULN in subjects with Gilbert syndrome, or total bilirubin \<3×ULN in subjects with indirect bilirubin indicating extrahepatic cause of total bilirubin elevation);

∙ ALT and AST≤ 2.5 times the upper limit of normal value; Patients with liver metastases do not exceed 5 times the upper limit of normal;

∙ Normal coagulation function (PT, APPT within 1.5 times the upper limit of normal);

‣ Female subjects of childbearing age must have tested serum-negative for pregnancy before receiving the first trial drug;

‣ Female subjects of reproductive age and male subjects with partners of women of reproductive age received effective forms of contraception during and for 3 months after treatment;

‣ For subjects with genital herpes, need 3 months after the end of herpes;

‣ Voluntary signing of informed consent, expected compliance is good.