Clear cell renal cell carcinoma (ccRCC) is the most common adult renal neoplasm and its incidence continues to increase. Collagen is the most abundant extracellular matrix protein in stroma, and contributes to the development and progression of ccRCC. We examined the human collagen type XXIII α1 chain (COL23A1) expression in ccRCC and the relationship between COL23A1 and patients' survival. We found COL23A1 mRNA was elevated in tumor compared with adjacent normal tissues, which was further validated by TCGA cohort. IHC results from 151 ccRCC cases suggested that high COL23A1 expression correlated with larger tumor size (P?=?0.017) and advanced T stage (P?=?0.011). The overall survival (OS) was shorter for ccRCC patients with high COL23A1 expression (P?=?0.002). In multivariate analysis, high COL23A1 expression was an independent prognostic factor of OS (HR: 3.024, P?=?0.017). Furthermore, COL23A1 knockdown repressed proliferation of ccRCC cell lines by blocking cell cycle progression. Cell adhesion and migration capacity was also downregulated by knockdown of COL23A1. Our data indicate that COL23A1 may be a novel prognostic indicator in ccRCC and might be a specific and accessible biomarker as well as a potential new target for clinical diagnosis of ccRCC.