A large body of literature has examined and described galectin expression in cancer. Discrepancies have been observed in the reported data, which hampered clear understanding of the expression profiles. This relates to the use of different types of methods that evaluate either global or specific gene expression in heterogeneous cancer tissue samples, type of antibodies used in immunohistochemistry and procedures of comparison of gene expression. In this manuscript, we review the main data concerning expression of galectins in human cancer. Only galectin-1 and galectin-3, the most abundant and examined galectins, will be examined here.