Caspase cysteine proteases are factors widely recognized for their role in the induction of apoptotic cell death. Caspases induce apoptosis during the inflammatory response to pathogen infection; in addition, caspases such as caspase-1 and caspase-11 are known to be involved in the production of inflammatory cytokines in response to bacterial infections. Caspase-1 is activated in the inflammasome, an intracellular protein complex that is formed by the recognition of intracellular ligands or cellular stresses by sensor molecules such as NOD-like receptors. Under certain conditions, caspase-11 is required for the activation of the caspase-1 inflammasome, referred to as the non-canonical inflammasome. In addition to these caspases, accumulating evidence indicates that caspase-8 also contributes to the production of inflammatory cytokines. In contrast to caspase-1, caspase-8 is activated by receptors located on the plasma membrane including dectin-1, TLR-3/4, and Fas. Recently, Fas-mediated caspase-8 activation and inflammatory cytokine production have been shown to play a significant role in the regulation of bacterial infections. This review highlights the functional roles and activation mechanisms of caspase-1/-11 in innate immune responses against bacterial infection. In addition, we discuss the novel aspects of caspase-8 function in comparison with caspase-1/-11 during innate inflammatory responses.