MAIT cells are a recently recognised innate-like T-cell subset which express a semi-invariant T-cell receptor (Vα7.2-Jα12/20/33) and are restricted to antigen presented by the evolutionary conserved, non-polymorphic MHC class I related protein, MR1. MR1 presents unstable derivatives of precursors of riboflavin, triggering MAIT cell activation via their T-cell receptor (TCR). They can also be activated via their cytokine receptors, mainly by IL-12 and IL-18. However, it is unclear how the effector function of human MAIT cells differ in response to different stimuli. In this study, we investigated the effector function of MAIT cells to E. coli, soluble ligand (5-A-RU) and cytokines (IL-12+IL-18). We observed rapid activation of human MAIT cells and significant cytokine production against all stimuli, although significant TNF-α production was only observed when MAIT cells were activated via their TCR by E. coli or 5-A-RU. Differences in timing of maximal activation were seen with different stimuli, both at the protein and transcriptomic levels. To explore the effector functions of activated MAIT cells and further outline the differences between the two modes of activation, RNA sequencing was performed on MAIT cells stimulated with E. coli, 5-A-RU or IL-12+IL-18. Differences in MAIT cell response were observed in cytokine and chemokine production and the profile of cytotoxic molecules expressed. Overall, this suggests that the effector function of MAIT cells differs depending upon the mode of activation.