Abstract: The price of biodiesel is approximately 15 times higher than that of traditional diesel. It is urgent to explore cheaply available substrates to reduce the cost of biodiesel production. As one of the cheap and widespread wastes， lignocellulose contained cellulose and hemicellulose which could be hydrolyzed and used in the fermentation of biodiesel. The genetic engineered strain Escherichia coli pET28a(+)PAW fermented straw hydrolysates into alcohol， and further into biodiesel with fatty acids by onestep transformation invivo. The HPLC analysis showed that the corn straw hydrolysate had a higher glucose concentration (1040 g·L-1) and the wheat straw hydrolysate had a higher xylose concentration (4056 g·L-1). When straw hydrolysates were utilized as sugar substitutes for biodiesel production by E. coli pET28a(+)PAW， the maximum biodiesel yield of 030 g·L-1 (wheat hydrolysate) was obtained which is higher than the yield of biodiesel 025 g·L-1 (corn hydrolysate) and the present reports. The straw hydrolysates could be utilized by genetic engineering strain as the substrates for biodiesel production， to reduce the material price of biodiesel.

Key words: fatty acid ethyl esters, biodiesel, Escherichia coli pET28a(+)PAW, straw hydrolysates