Background: Advanced gastrointestinal (GI) tumors, such as colorectal, gastric and pancreatic cancers (CRC, GC, and PC), and esophageal squamous cell carcinoma (ESCC), 20%-50% with liver metastases (LMs) have a poor prognosis. Previous trials showed that anlotinib plus chemotherapy has promising clinical activity and a tolerable safety profile for advanced CRC and ESCC, especially with LMs. In this phase II trial, we assessed the efficacy and safety of anlotinib plus chemotherapy as first-line treatment for LMs GI tumors. Methods: Patients with unresectable LMs GI tumors and without previous systemic treatment would be divided into cohort A (CRC), cohort B (ESCC), and cohort C (other GI tumors, such as PC, GC, biliary tract cancer (BTC), etc.). In cohort C, patients received induction therapy: anlotinib plus standard chemotherapy. Patients without PD and radical resection received anlotinib and metronomic capecitabine (500 mg, PO, BID, days 1-21, q3w) maintenance until PD or unacceptable toxicity. The primary endpoint was ORR (RECIST 1.1). Secondary endpoints were DoR, PFS, OS, DCR, radical resection rate for LMs, and safety. Results: As of September 14, 2023, 41 patients were enrolled in cohort C (29 PC, 6 GC, 5 BTC, and others), the median age was 64 years (34-74), 63.4% male, 92.7% ECOG-PS 1 and 56.1% had LMs only. The majority of the pancreatic cancer patients (26/29) received gemcitabine plus nab-paclitaxel chemotherapy combination with anlotinib as induction therapy. After induction therapy, 4 patients (1 PC, 2 GC, 1 BTC) received surgical resection. Of 37 evaluable patients in cohort C, ORR and DCR were 45.9% and 86.5% (PR, n=17; SD, n=15, 12 SD had reduced tumor size). Of 25 evaluable pancreatic cancer patients, 12 had PR, 10 had SD, ORR and DCR were 48% and 88%. According to the Kaplan-Meier method, the median DoR was 4.2 months (95%CI, 1.7-6.6) and the median PFS was 5.5 months (95%CI, 4.7-6.3). 37 patients in cohort C had TEAEs and ≥ grade 3 TEAEs (51.2%) mainly included neutropenia (19.5%), white blood cell decreased (12.2%), and blood platelet decreased (9.8%). Conclusions: Anlotinib plus chemotherapy as first-line treatment has shown promising efficacy and acceptable safety and maybe a favorable option for advanced LMs GI tumors, especially for pancreatic cancer. Clinical trial information: NCT05262335.