In recent years the research on the roles of eukaryotic mRNA 3′UTR in suppression of malignant phenotype of tumor cells has achieved very exciting advances. It has been found that the 3′UTR is involved in regulation of function of known oncogenes and antioncogenes; that the inactivation of some antioncogenes came from the structural changes of their 3′UTR; and that the 3′UTR of several genes exerted antioncogene activity after transfection into malignant cells. Apart from these, further studies have also been performed on the roles of 3′UTR in regulation of mRNA expression. Recent advances of part of studies in this field are reviewed.