This research developed a novel, efficient and safe antimildew for peanut kernel postharvest storage. The antimildew, cinnamon-Litsea cubeba compound essential oil (CLCEO) microcapsule (CLCEOM), was synthesized with CLCEO as core materials and β-cyclodextrin as wall materials. Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry analyses indicated that major antifungal compounds of CLCEO were encapsulated in the cavity of β-cyclodextrin. The inhibition zone experiment showed that CLCEOM retained antifungal effect on Aspergillus spp. strains even after storage for 2 months at 4 ℃. Besides, CLCEOM reduced total number of fungal colonies, relative abundance of Aspergillus spp., and aflatoxin B1 content of peanut kernels, and had positive effect on slowing down the increase in acid value of peanut oil without causing any adverse effect on the viability and sensory properties during storage process. Overall, CLCEOM presented good preservative effects on peanut kernels, providing evidence for its potential use as antimildew for peanut storage.