Euphopias A-C (1-3), three rearranged jatrophane-type diterpenoids with tricyclo[8.3.0.02,7]tridecane (1 and 2) and tetracyclo[11.3.0.02,10.03,7]hexadecane (3) cores, were isolated from Euphorbia helioscopia. Comprehensive spectroscopic analyses, quantum-chemical calculations, and X-ray diffractions were used to identify their structures. Compounds 1-3 could significantly inhibit NLRP3 inflammasome activation and block NLRP3 inflammasome-induced pyroptosis. Additionally, a mechanistic study revealed that 2 could ameliorate mitochondria damage, thereby interrupting NLRP3 inflammasome activation.