Colorectal cancer (CRC) is one of the most common cancers worldwide. Long non-coding RNAs (lncRNAs) have been shown to play important regulatory roles in cancer biology, and functional lncRNAs can be used for cancer diagnosis and prognosis. One lncRNA that has attracted significant attention is urothelial carcinoma-associated 1 (UCA1), which is significantly up-regulated in most tumour tissues and cancer cells. However, the contributions of UCA1 to CRC remain largely unknown. Thus, the aim of the current study was to investigate the clinical significance and biological function of UCA1 in CRC.First, we evaluated whether UCA1 is detectable or altered in CRC tissues or cell lines compared to adjacent normal tissues or normal cell lines by quantitative real-time polymerase chain reaction. The potential relationship between UCA1 levels in tumour tissues and the clinicopathological features of CRC was then investigated. Finally, we assessed whether UCA1 influences cell proliferation, apoptosis, cell cycle distribution and migration in vitro.Our results demonstrated that UCA1 levels were markedly increased in CRC tissues and cells compared to controls, and this high level of UCA1 expression was significantly correlated with larger tumour size, less differentiated histology and greater tumour depth. In addition, patients with high UCA1 expression had a significantly poorer prognosis than those with low UCA1 expression. Moreover, UCA1 was found to influence the proliferation, apoptosis and cell cycle progression of CRC cells. These data suggest an important role for UCA1 in the molecular aetiology of CRC and suggest a potential application for UCA1 in CRC diagnosis, progression and therapy.