There are studies reporting that glucoside xylosyltransferase 2 (GXYLT2) has a role in promoting tumor progression, but its role in clear cell renal cell carcinoma (ccRCC) remains unclear. In this study, RT-qPCR and western blotting were employed to detect the expression level of GXYLT2. RNA interference assays were used to knock down GXYLT2. CCK-8, wound healing assays, clone formation assays, and Transwell assays were utilized to investigate the function of GXYLT2. Bioinformatics analysis was used to explore the tumor microenvironment and potential biological mechanisms. We found that the expression level of GXYLT2 in ccRCC was higher than that in adjacent normal renal tissues. Patients with high GXYLT2 expression have worse clinical outcomes. Knockdown of GXYLT2 inhibits the proliferation, invasion, migration, and clone formation ability of ccRCC cells. Enrichment analysis uncovered that GXYLT2 participates in Wnt, cell cycle, and actin cytoskeleton regulation signaling pathways. After receiving anti-PD-1 therapy, patients with high GXYLT2 expression had longer progression-free survival compared with those with low GXYLT2 expression. In conclusion, GXYLT2 is a novel potential therapeutic target for ccRCC. Meanwhile, GXYLT2 can be used as a novel marker for predicting immunotherapeutic response.