Abstract: Ferulic (FA)-niacinamide (NIC) cocrystals were prepared and the hydrogen bonding interactions between FA and NIC in cocrystalline state and aqueous solution were studied. The solubility and UV light stability of FA-NIC cocrystals were analyzed. Infrared spectra and Hirshfeld surface analyses of FA-NIC cocrystals indicated that the FA-NIC cocrystals assembled via hydrogen bonds between FA and NIC in four locations, and the intensity of the hydrogen bonds was ranked as follows: Ⅲ(O—H···O)>Ⅰ≈Ⅱ(O···H—N)>Ⅳ(O···H—C). Compared to free FA, FA-NIC cocrystals showed lower ultraviolet absorption and fluorescence intensity in aqueous solution, which suggested that the FA-NIC cocrystals did not dissociate into individual components completely and that the hydrogen bonds between NIC and FA retained in aqueous solution. By cocrystallization with NIC, the solubility of FA increased by approximately 88%, and the UV light stability of FA increased by 12.7%. This suggested that FA was easy to be solvated and difficult to change its configuration due to the hydrogen bonds between FA and NIC in cocrystals. Thus, the solubility and UV light stability of FA were demonstrated to improve remarkably by cocrystallization with NIC, which was predominantly determined by the hydrogen bonding interactions between FA and NIC.