Inclusion Criteria:  Volunteer to participate and sign the informed consent form. Age ≥ 18 years old, regardless of gender. Patients with unresectable or metastatic advanced solid tumors confirmed by histology or cytology.  Failure or intolerance of the standard treatment recommended by the guidelines for various tumor types.  Note: If recurrence occurs during adjuvant/neoadjuvant therapy or within 6 months after completion, adjuvant/neoadjuvant therapy is considered to be the first-line treatment for advanced disease.  Have not received immune checkpoint inhibitor treatment. Patients with the following tumor types: small cell lung cancer, cervical cancer, endometrial cancer, ovarian cancer, vulvar cancer, neuroendocrine tumors, salivary gland cancer, thyroid papillary or follicular cancer, skin squamous cell carcinoma, skin malignant melanoma , Merkel cell tumor, head and neck squamous cell carcinoma, colorectal cancer, gastric cancer, bladder cancer, cholangiocarcinoma, etc. Tissue and blood samples with detectable TMB; tissue samples need to be from lesions that have not received local radiotherapy (special cases can be considered after discussion with the sponsor and approval). The tumor tissue submitted for analysis must be from a single tumor tissue specimen. There is at least one measurable lesion (RECIST 1.1 standard). ECOG score of 0 or 1. The expected survival period is ≥ 12 weeks.  Sufficient organ and bone marrow function (no hematopoietic growth factor, blood transfusion or platelet therapy was given within 7 days before the first study drug treatment):  Blood routine: absolute neutrophil count (ANC) ≥1.5×109/L, platelet ≥100×109/L and hemoglobin ≥90 g/L; Liver function: serum total bilirubin ≤ 1.5 times the upper limit of the normal reference range (×ULN); when there is no liver metastasis, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤ 2.5 × ULN; ALT and AST ≤5 × ULN in liver metastasis; Renal function: subjects with serum creatinine ≤ 1.5 × ULN or creatinine level> 1.5 times ULN, measured or calculated according to Cockcroft-Gault formula creatinine clearance rate ≥ 60.0 mL / min; Coagulation function: International normalized ratio (INR) ≤ 1.5 and partially activated prothrombin time (aPTT) ≤ 1.5 × ULN; (For patients undergoing anticoagulation therapy, the investigator judges that both INR and aPTT are safe and effective treatments Within); Heart function: left ventricular ejection fraction (LVEF) detected by echocardiography>50% Women with fertility must have a negative serum pregnancy test within 7 days before the first medication. Reproductive male or female patients voluntarily use effective contraceptive methods, such as double-barrier contraceptive methods, condoms, oral or injectable contraceptives, intrauterine devices, etc., from signing the informed consent until 90 days after the last study medication. All female patients will be considered fertile unless the female patient has been naturally menopausal, has undergone artificial menopause, or has been sterilized (such as hysterectomy, bilateral adnexectomy).  Exclusion Criteria:  Participate in the clinical trials of other investigational drugs or investigational devices within 28 days before the first medication; or have received anti-tumor treatment within 2 weeks, including but not limited to chemotherapy and radiotherapy (allowed to complete the palliative at least 1 week before the study drug treatment Radiotherapy) or targeted therapy.  The toxicity of previous anti-tumor treatments has not recovered to 0 or 1 level (hair loss, peripheral neurotoxicity caused by chemotherapy ≤ 2 can be selected). Subjects who need to use corticosteroids (> 10 mg/day prednisone equivalent dose) or other immunosuppressive drugs for systemic therapy within 14 days before the study drug is administered.  Note: If there is no active autoimmune disease, inhaled or topical steroid hormones, or adrenal hormone replacement therapy with a prednisone equivalent dose of ≤ 10 mg per day is allowed. Allow short-term (≤ 7 days) use of glucocorticoids for preventive treatment (for example, for subjects with a history of severe allergies, when other anti-allergic drugs cannot be used instead to prevent allergy to contrast agents, researchers can use glucocorticoids according to local diagnosis and treatment routines Prevention) or for the treatment of non-autoimmune diseases (for example, delayed type hypersensitivity caused by contact allergens).  Subjects who have active, or have had autoimmune diseases or risks that may recur (for example, an organ transplant that requires immunosuppressive therapy). However, subjects with type I diabetes, hypothyroidism requiring only hormone replacement therapy, or skin diseases that do not require systemic treatment (for example, vitiligo, psoriasis, or hair loss) are allowed to be included in the group. For any uncertain situation, it is recommended to consult the sponsor's medical monitor before signing the informed consent. Major surgery (except for biopsy) or the surgical incision did not heal completely within 4 weeks before the first study drug treatment. Suffered from other known malignant tumors within 2 years before enrollment (except for treated skin basal cell carcinoma, skin squamous cell carcinoma and/or carcinoma in situ after radical resection). Symptomatic brain metastasis or spinal cord compression; for patients with brain metastases who have previously received treatment, if the clinical and imaging evidence does not indicate disease progression within 4 weeks before the first study drug treatment, and 2 weeks before the first administration There is no need to receive corticosteroid treatment and can be considered for inclusion.