Blakeslea trispora, a filamentous fungus, was cultured both in a 15lit stirred tank and 75lit airlift bioreactor. Different rates of aeration and agitation were investigated in related bioreactors in order to find the more appropriate culture conditions for better production of ?-carotene. The results showed that the ?-carotene production by Blakeslea trispora is highly dependent on the degree of aeration of culture medium. ?-carotene yield was enhanced up to 120mg/L when the aeration and agitation rate was increased in stirred bioreactor, up to 2vvm and 400rpm, respectively. However, under similar aeration condition, the production of the desired product was about 0.7 times more in airlift than the stirred bioreactor.