Inclusion Criteria:
* 1\. Pathological diagnosis as malignant tumor of Intrahepatic Cholangiocarcinoma;
* 2\. According to the UICC/AJCC TNM staging system (8th edition, 2017), resectable subjects were classified as Ib-IIIb stages;
* 3\. aged ≥ 18 years at the time of signing the Informed consent form (ICF);
* 4\. Expected survival time\>3 months;
* 5\. Both men and women are eligible;
* 6\. The patient's Eastern Oncology Collaborative Group (ECOG) physical condition score is 0 or 1;
* 7\. No serious complications, such as hypertension, coronary heart disease, or history of mental illness, and no history of severe allergies; Non pregnancy and non lactation period;
* 8\. The organ and blood system functions of the subjects meet the following requirements:
1. Absolute neutrophil count (ANC) ≥ 1.5 × 10 \^ 9/L;
2. Platelet count ≥ 75 × 10 \^ 9/L;
3. Hemoglobin ≥ 90 g/L;
4. Serum total bilirubin ≤ 1.5 x upper limit of normal (ULN);
5. Aspartate aminotransferase (AST) and alanine aminotransferase ≤ 2.5 x ULN;
6. Albumin ≥ 3g/dL
7. Creatinine ≤ 1.5 x ULN
* 9\. The subjects can understand and sign the informed consent form to participate in the experimental study; Good compliance.
* 10\. Participants who have not undergone any local or systemic treatment for tumors in the past, and have undergone radical resection surgery for biliary tract cancer before recurrence for at least 2 years, can be included;
* 11\. Subjects with potential fertility need to use a medically approved contraceptive measure (such as an intrauterine device, contraceptive pill, or condom) during the study treatment period and within one month after the end of the study treatment period; And within 72 hours before enrollment, the serum or urine HCG test must be negative and must be non lactating;
Exclusion Criteria:
* 1\. Patients who received PD-1, PD-L1, PD-L2, or CTLA-4 inhibitors before enrollment, or patients who directly received another stimulating or co inhibitory T cell receptor (such as CTLA-4, CD137);
* 2\. Use any other investigational drugs within 4 weeks prior to enrollment;
* 3\. Any history of active autoimmune diseases or autoimmune diseases (such as interstitial pneumonia, uveitis, enteritis, hepatitis, pituitary inflammation, vasculitis, myocarditis, nephritis, hyperthyroidism, hypothyroidism after hormone replacement therapy); Children with asthma who have completely improved in adulthood and do not require any intervention can be included, but patients who require intervention with bronchodilators cannot be included;
* 4\. Congenital or acquired immunodeficiency, such as infection with human immunodeficiency virus (HIV), active hepatitis B (HBV DNA 500IU/ml), hepatitis C (hepatitis C antibody positive, HCV-RNA above the detection limit of the analysis method), or co infection with hepatitis B and hepatitis C;
* 5\. Serious infection (such as intravenous infusion of antibiotics, antifungal or antiviral drugs) occurred within 4 weeks before the first administration, or unexplained fever\>38.5 ° C occurred during screening/before the first administration;
* 6\. History of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation;
* 7\. Suffering from uncontrollable mental illness;
* 8\. The simultaneous occurrence of serious and/or uncontrollable diseases may affect the participation of the study, such as unstable angina pectoris, myocardial infarction within 6 months, unstable symptomatic arrhythmia, symptomatic congestive heart failure, poorly controlled diabetes, serious activities, uncontrollable infection after insufficient biliary drainage (such as tumor blocking the bile duct);
* 9\. Pregnancy (positive pregnancy test) or lactation period;
* 10\. Other cancers that have occurred in the past (within the past 5 years) or simultaneously, excluding non melanoma skin cancer and in situ cancer;
* 11\. History of allergy or hypersensitivity to any investigational drug;
* 12\. Currently abusing alcohol or illegal drugs;
* 13\. Unable or unwilling to sign informed consent form.
