Background: Anti-programed cell death-1 (PD-1) monotherapy is a part of the standard treatment for cutaneous melanoma, but its efficacy in mucosal melanoma is not ideal. In vivo studies have demonstrated that co-inhibition of the VEGF receptor (VEGFR) and PD-1 pathways increased T cell infiltration and suppressed tumor growth synergistically. Early phase trial data confirmed that PD-1 inhibitors combined with anti-angiogenic drugs showed efficacy in the treatment of advanced mucosal melanoma, but still did not meet clinical needs. Previous studies have shown that chemotherapy combined with anti-angiogenic drugs has significantly improved median PFS and median OS compared with chemotherapy alone, and has a certain effect as a salvage treatment for progression after PD-1 inhibitor treatment. In addition, previous retrospective analysis showed that PD-1 inhibitors combined with chemotherapy drugs such as nab-paclitaxel were superior to anti-PD-1 monotherapy in the treatment of advanced mucosal melanoma. In summary, the combination of anti-PD-1, anti-angiogenic drugs and chemotherapy may bring new hope for the treatment of advanced mucosal melanoma. Methods: This is a single-arm, multicenter, exploratory study to evaluate the efficacy and safety of camrelizumab combined with anlotinib and nab-paclitaxel as first-line therapy in patients with advanced mucosal melanoma. The trial is expected to enrol 66 patients. Key Inclusion Criteria are pts with confirmed recurrence, unresectable or metastatic mucosal melanoma after surgery (stage III/IV) and ECOG performance status of ≤1.Pts with previous adjuvant therapy or neoadjuvant therapy (except PD-1/PDL1 monoclonal antibody and VEGFR TKI) at least 4 weeks before the first administration of the study drug are allowed. Patients received intravenous camrelizumab (200 mg) on day 1, intravenous nab-paclitaxel (260mg/m²) on day 1, and oral anlotinib (8mg) on days 1-14 every 3 weeks. The primary endpoint is objective response rate (ORR). Secondary endpoints include disease control rate (DCR),progression-free survival (PFS), and 2-year overall survival (OS). Clinical trial information: NCT04979585.