Arisaema sikokianum Franch. et Sav. (Araceae) is one of the most beautiful ornamental Arisaema species. Species in this genus demonstrate a unique sexual dimorphism based on corm size. When the corm size is small the sex expression is male, and it changes to female as the corms enlarge. Because of this strict size-based sexual dimorphism, there is no experimental evidence that Arisaema species are capable of self-fertilization. Pollen harvested from several different male plants of A. sikokianum was stored at 4°C, -20°C in a cryostat, and -196°C in liquid nitrogen (LN₂) for 30 days, 6 months, and 1 year. Then the viability of the pollen was estimated by pollen germination. Only the pollen stored in LN₂ retained high viability after one year of storage. In order to verify self-compatibility in A. sikokianum, pollen that was collected from several male plants and cryopreserved for a year was used to pollinate the same plants when the sexual expression of the plants converted to female. Both self- and cross-pollinated spadices produced seeds, indicating that A. sikokianum is self-compatible. Self-pollinated spadices produced fewer fruits with fewer seeds compared with cross-pollinated spadices. Self-pollinated seeds germinated more slowly at 20°C in the dark. No clear differences in corm weight were observed between self- and cross-pollinated seedlings.