Abstract:By use pentad precipitation data at 25 stations in Liaoning Province from 1960 to 2005, the characteristics of the spatial temporal distribution and variation of the precipitation are analyzed，in terms of the precipitation conce ntration degree (PCD) and precipitation concentration period (PCP). Meanwhile, t he comparison of the PCD is also made between rainy years and dry years. 　　The results show that the PCD and PCP can demonstrate the inhomogeneity of q uantitative precipitation in spatial temporal distribution. The mean PCD in al l stations is 0.655, with the maximum of 0.749, and the minimum of 0.509. The mean of PCP is 40.953 pentad, with the maximum of 45.221 pentads, the minimum of 37 .697 pentads. The trend of both annual PCD and the PCD in flood season diminishe s. The diminishing trend of the PCD in flood season is obvious. The EOF of norma lized anomaly fields of the PCD shows that the three EOF modes can depict the sp atial distribution. The first principal component exhibits all the stations inph ase. The second principal component takes on seesaw between the southeast and no rthwest areas. The synthetic analysis of more and less precipitation showed that PCD in years with more precipitation is obviously larger than that of less prec ipitation, besides, the distribution of the PCD is more complicated in rainy yea rs than in dry years.