Pigment extracts obtained from Star Ruby grapefruit pulp were stored at different temperatures (4.5$^{circ}C$, 23$^{circ}C$) and exposed to light. many carotenoid oxidation products were formed due to light-exposure during storage periods. They were monitored by using HPLC with photodiode array detection and tentatively identified. Including (all-E)-lycopene and trans-$eta$-carotene as predominant carotenoids in red grapefruit, 5Z-lycopene, 9Z-lycopene, 13Z-lycopene, and 15-cis-$eta$-carotene were formed at 4.5$^{circ}C$, 23$^{circ}C$. Degradation of all-tarns lycopene was more susceptible to light-exposure and temperature a than that of all-trans $eta$-carotene. The formation of lycopene cis isomers was favored under lighted condition. Respectively, (5Z)-lycopene was formed in greater amounts than other isomers at 23$^{circ}C$ storage. The concentration of 15-cis-$eta$-carotene was significantly increased during storage at 23$^{circ}C$ storage. The concentration of 15-cis-$eta$-carotene was significantly increased during storage at 23$^{circ}C$.