Abstract: An inflammasome activates caspase-1 for cytokine maturation and cell death, and thus induces host defense in cells. An NLRP3 inflammasome promotes the release of highly inflammatory cytokines IL-1? and IL-18 to induce gasdermin D-mediated pyroptosis (pyroptotic cell death), and thus is involved in inflammatory processes. Therefore, targeting an NLRP3 pathway and modulating relevant immune responses can be a promising strategy for designing drug candidates for inflammatory diseases. A rationally designed ?2-helix-based peptide NIP3 inhibits the NLRP3 pathway. NIP3 has remarkably inhibited both the secretion of NLRP3-induced IL-1? and IL-18 and the expression of downstream proteins in lipopolysaccharide-primed nigericin-activated THP-1 cells. In addition, binding energy data suggests that NIP3 has a stronger affinity for ASCPYD than for NLRP3PYD. Therefore, according to empirical and in silico results, NIP3 exclusively inhibits the NLRP3-ASC-caspase-1 pathway.