Two commercial serological kits (Oxoid BCET-RPLA and Tecra VIA) and a Chinese hamster ovary (CHO) cell cytotonicity assay for the detection of Bacillus cereus diarrhoeal enterotoxin were compared. Eleven B. cereus strains and one enterotoxigenic B. thuringiensis strain were evaluated. Both kits and the CHO cell assay yielded positive toxin responses for cell-free culture filtrates from eight out of 11 diarrhoeal enterotoxigenic strains. An emetic enterotoxin producing strain was negative with all three assays. Two B. cereus strains were negative using the BCET-RPLA kit, but positive with the Tecra VIA kit and CHO cell assay. The BCET-RPLA indicated significant levels of enterotoxin after samples were boiled, whereas the CHO cell and Tecra assays were negative. Overall, the cell culture assay was the most sensitive. However, the Tecra VIA kit provided similar results and was better suited for the rapid detection of B. cereus diarrhoeal enterotoxin.