A strain CG08 was isolated which could selectively hydrogenate cinnamaldehyde to cinnamyl alcohol. The strain was idetified as Citrobacter freundii. The yield of cinnamyl alcohol was determined by UV spectroscopy. The optimized degradation conditions were found as 30 g/L glucose,16 g/L peptone with the initial cinnamaldehyde addition amount of 2 mL/L at pH 6.0, 30 °C for 40 hours of reaction. The secondary addition amount was 1 mL/L for 32 hours. Under the optimized conditions, the conversion of cinnamaldehyde was 100 %, the selectivity for cinnamyl alcohol was 90.1 %. And the yield of cinnamyl alcohol was up to 2.88 g/L, which was 26.3 % higher than the previously reported one.