Inclusion Criteria:
* 1\. Age 18-75 years old, gender unlimited;
* 2\. Histologically or cytologically confirmed pancreatic ductal adenocarcinoma (PDAC);
* 3\. Locally advanced pancreatic cancer (according to the NCCN criteria), unresectable or surgically declined;
* 4\. The maximum diameter of the primary tumor was \< 5.0cm;
* 5\. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1;
* 6\. No prior radiotherapy (upper abdomen) or tumor systemic therapy;
* 7\. Adequate organ and bone marrow function, defined as follows: absolute neutrophil count (ANC)≥1.5×10\^9/L; hemoglobin≥9.0 g/dL; platelets≥75×10\^9/L; serum total bilirubin (TBIL)≤1.5×ULN; aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤ 2.5 times the upper limit of normal (ULN); serum creatinine≤1.5×ULN;
* 8\. Left ventricular ejection fraction ≥50%;
* 9\. Fertile subjects are willing to take contraceptive measures during the study period;
* 10\. Woman who are breastfeeding during the study period or within 150 days after the last treatment;
* 11\. Survival was expected to be ≥3 months;
* 12.Good compliance and signed informed consent voluntarily.
Exclusion Criteria:
* 1\. Tumor invasion of gastrointestinal tract;
* 2\. Woman who are pregnant or breastfeeding;
* 3\. History of other malignancies (except cured basal cell carcinoma of the skin and carcinoma in situ of the cervix) within the past 5 years;
* 4\. History of uncontrolled epilepsy, central nervous system disease, or mental disorder, which may influence the signing of informed consent or affect the patient's adherence;
* 5.Serious heart disease, such as symptomatic coronary heart disease, New York Heart Association (NYHA) class II or more, severe congestive heart failure or severe arrhythmia requiring medical intervention, or a history of myocardial infarction within the past 12 months;
* 6\. Patients requiring immunosuppressive;
* 7.Accompanied by active infections, or a major hematological, renal, metabolic, gastrointestinal, endocrine, or metabolic disorder determined by the investigator, or other serious uncontrolled concomitant disease;
* 8\. Known allergy to prescription or any component of the prescription used in this study;
* 9\. Immunodeficiency, including HIV infection or other acquired immunodeficiency, or a history of organ transplantation, or other immune-related disorders requiring medical intervention;
* 10\. Patients with acute and chronic tuberculosis infection;
* 11\. Received Chinese herbal medicines or immune-modulators for anti-tumor within 2 weeks prior to initial administration;
* 12.History of noninfectious pneumonia requiring glucocorticoid therapy or current interstitial lung disease within 1 year prior to initial administration;
* 13\. Received any other form of immunosuppressive therapy within 7 days prior to the initial of study administration;
* 14\. Participated in other clinical trials within 4 weeks, or received another investigational drugs or investigational device within 4 weeks prior to the initial administration;
* 15.Other reasons that are not suitable to participate in this study according to the researcher's judgment.
