The effects of fluoresescent light on the quanlity parameters of crude Silybum marinum oil (SMO) and crude helianthus annuus (sunflower)oil (HAO) were studied. The quanlity constants monitored were free fatty acid (FFA), iodine value (IV), peroxide value (POV), anisidine value (AV), colour (OD) and b-carotene. Results revealed an increase in FFA,  POV,  AV after stronge under continuous fluorescent light irriadiation. However, OD ant IV decresed in both oils under the test condition. More decrease in colourswas observed in Silybum marinum oil than helianthus annuus oil, while a reverse trend was found in iodine value. The decrese in b-carotene concentreation in both oils remained almost same. The crude silybum maranum oil is found to be very sensitive to oxidiation when exposed to flurescent light than the crude Helianthus annus oil