Abstract: To enhance the WUE of crops, a pot experiment was conducted to investigate the effect of ferulic acid on the water use efficiency of different wheat varieties. The results showed that: spray of 100 μmol/L FA on leaves promoted the Pn and WUE at low soil water content, but inhibited the Pn, Tr, Gs and WUE at high soil water content. These results suggested that, FA (100 μmol/L) could increase WUE in wheat cultivars.