MAIT cells are MR1-restricted T cells that are well-known for their anti-microbial properties, but they have recently been associated with different forms of cancer. Several studies have reported MAIT cells within the microenvironment of colorectal tumours, but there is conjecture about the nature of their response and whether they are contributing to either anti-tumour immunity or the progression of the disease. When investigating MAIT cell responses in stimulation conditions similar to those found within the colorectal cancer microenvironment we discovered previously unidentified cytokine responses, including potent IL-13 expression. This unexpected finding has important implications for IL-13-dependent diseases, such as colorectal cancer (CRC), that occur in mucosal areas where MAIT cells are abundant. We have also identified that exposing healthy donor PBMCs to soluble products from colorectal cancer cells resulted in a marked suppression of antigen mediated MAIT cell TNF responses. Our data suggest that MAIT cells have a more complicated role in CRC than currently realized and that they represent a promising new target for immunotherapies.