Many factors influence survival in colorectal cancer patients, one of them is the mucinous component of the tumour. Mucinous adenocarcinoma is characterized by the extracellular mucin of more than 50% of the tumour volume. From 1970 to 1999, 1160 patients were admitted to our clinic for colorectal cancer. They were divided into four groups according to mucinous character of the tumour, in two time periods of 15 years. There was an increase in the incidence of mucinous tumours from 20.8 to 30.5% in the second period. These tumours were more advanced (Dukes’ C) and especially right sided (34.5% vs. 17.9%). Five-year survival was increased during the second period but was of a lesser degree in the mucinous group (51.5% vs. 65.5%). Colorectal mucinous carcinomas present at a more advanced stage, predominantly in men, with higher right colon location rate, and a worse overall 5-year survival rate than the non-mucinous colorectal cancers.