Abstract: The carrot was used as raw material fermented by starter cultures rich in lactic acid bacteria. The fermentation conditions ( fermentation time, fermentation agent dosage and temperature) of carrot puree were optimized by response surface method.The results showed that the optimal fermentation conditions of carrot puree were as follows, fermentation for 27 h with fermentation agent dosage of 0.16 g at 40 ℃. Under this condition, the total acid, p H, total sugar, reducing sugar and total number of colonies of the fermentation carrot pulp were 5.5335, 3.99, 0.1287, 0.1198 g/L and 8.72 lg cfu/m L, respectively, which was close to the predictive value.34 and 33 volatile components were detected in carrot solution and fermentation broth, where obvious changes of volatile components were shown in the fermentation process.Fermentation broth of the carrots covered up for the original unpleasant carrot smell, which is a kind of new probiotic products that benefit health, so it should be promoted and extended.