Five previously undescribed clerodane diterpenoids named calintegerinoids A-E (1-5), featuring 5/6 and 6/6 fused ring systems, were isolated from Callicarpa integerrima. Their structures were determined using modern spectroscopic techniques, including NMR, HR-ESI-MS, IR, UV, specific rotations, and ECD, supplemented by quantum chemical calculations and DP4+ analysis. Compared with the standard drug Andrographolide (IC50 8.01 ± 0.46 μM), compound 3 demonstrated potent inhibition of LDH release with an IC50 value of 1.27 ± 0.05 μM. It also dose-dependently suppressed IL-1β release and potently blocked NLRP3 inflammasome activation triggered by LPS and Nigericin, leading to decreased pyroptosis. In addition, compound 3 decreased ASC speck formation in a dose-dependent manner, suggesting its significant anti-inflammatory potential by inhibiting NLRP3 inflammasome assembly.