Inclusion Criteria:  Patients with unresectable recurrent or metastatic adenocarcinoma of the colon or rectum confirmed histologically For subjects who have not previously received any systemic antitumor therapy and who have previously received neoadjuvant or adjuvant therapy, the first detection of recurrence or metastasis should be ≥12 months after the last administration of neoadjuvant or adjuvant therapy At least 1 measurable lesion according to RECIST V1.1 The vital organs are functioning well ECOG score is 0 ~ 1 Contraception was initiated from the signing of the informed consent until at least 6 months after the last dosing of the study drug  Exclusion Criteria:  Recurrent or metastatic lesions can be treated with radical surgery Presence of central nervous system or meningeal metastases; Moderate and severe ascites of clinical symptoms;Uncontrolled or moderate or greater pleural effusion or pericardial effusion Poorly controlled hypertension (systolic blood pressure ≥140 mmHg and/or diastolic blood pressure ≥90 mmHg in the case of regular antihypertensive therapy) and prior hypertensive crisis or hypertensive encephalopathy Severe cardiovascular and cerebrovascular diseases;Have clinical heart symptoms or diseases that are not well controlledSubjects with a history of myocardial infarction or unstable angina pectoris Subject with current interstitial pneumonia or interstitial lung disease, or with a previous history of interstitial pneumonia or interstitial lung disease requiring hormone therapy Previous treatment with targeted T cell costimulatory molecules and immune checkpoint inhibitors;Previous treatment with antiepidermal growth factor receptor or any antiangiogenic drug