In China， P-Ⅲ distribution is widely used in flood frequency analysis， but it is not suitable to be used under anynatural conditions. After the consistency modification of annual maximum daily discharge series， the EB-Ⅻ distribution is appliedto fit it at 17 hydrological gauging stations in the western Liaoning Province. and then be compared with nine distributions includingP-Ⅲdistribution to find the best fitting frequency distribution. The results indicate that the EB-Ⅻ distribution performs betterthan the other 9 distributions in validity and stability， and the T-year designed flood peaks of EB-Ⅻ distribution are moderate asthe peaks of the other frequency distributions may be higher or lower. Therefore， the EB-Ⅻ distribution is recommended to substituteP-Ⅲ distribution for frequency analysis in the western Liaoning Province.