A Study of TQB2450 Injection Combined With Stereotactic Body Radiation Therapy (SBRT) in Subjects With Advanced Oligometastatic Non-Small Cell Lung Cancer

Inclusion Criteria: * 1\. Eastern Cooperative Oncology Group (ECOG) performance status score of 0 to 2; Life expectancy ≥ 3 months. 2\. Histologically or pathologically confirmed advanced non-small cell lung cancer. 3\. Primary lesion controlled oligometastatic patients, the number of metastatic lesions ≤ 5, and has at least one measurable lesion. 4\. Has received standard first-line chemotherapy, intolerable or inappropriate to the chemotherapy. 5\. Adequate organ system function. 6. Male or female subjects should agree to use an adequate method of contraception starting with the first dose of study therapy through 6 months after the last dose of study (such as intrauterine devices , contraceptives or condoms) ；No pregnant or breastfeeding women, and a negative pregnancy test are received within 7 days before the first administration. 7.Understood and Signed an informed consent form. Exclusion Criteria: * 1\. Has used against PD-1, PD-L1 and other related immunotherapeutic drugs. 2.Has mutations in (epidermal growth factor receptor)EGFR, (anaplastic lymphoma kinase)ALK, (c-ros oncogene 1 receptor kinase)ROS1 or T790M and not resistant to targeted drug. 3\. Has severe hypersensitivity reaction to other monoclonal antibodies. 4. Has diagnosed and/or treated additional malignancy within 5 years prior to the first administration.Exceptions include cured basal cell carcinoma of skin and carcinoma in situ of cervix. 5\. Has any active autoimmune disease or a history of autoimmune disease. 6. Immunosuppressive therapy with immunosuppressive agents or systemic or absorbable local hormones (dosage \> 10 mg/day prednisone or other therapeutic hormones) is required for the purpose of immunosuppression, and is still in use for 2 weeks after the first administration. 7\. (Magnetic Resonance Imaging)MRI examination found meningeal metastases and cannot be controlled by stereotactic radiotherapy. 8\. Has adverse events caused by previous therapy except alopecia that did not recover to ≤grade 1. 9\. Has any severe and/or uncontrolled disease. 10. Has vaccinated with vaccines or attenuated vaccines within 4 weeks prior to first administration. 11\. According to the judgement of the researchers, there are other factors that may lead to the termination of the study.