The study area is in the southern part of Liaohe-River plain,which has a temperate continental monsoon climate : it is cold and dry in winter, and warm and wet in summer. According to the technology of dendrochronology, a total of 233 cores (1 to 3 cores per tree) were taken from 126 Pinus tabulaeformis trees from two sites: Qianshan (41°11'23"N, 123°08'01"E; 520m a.s.l.; 70 trees/136 cores), which belongs to semi-humid region with exuberant vegetation), and Lushan (41°36'35〃N, 121°41'42"E; 415m a.s.l. ; 56 trees/97 cores) is located at a semi-arid area with less vegetation as compared to Qianshan. The crossdating was checked using COFECHA after dried, mounted, surface sanded, corssdated and ring width measured (with a precision of 0.01mm) process. Using the program ARSTAN, three kinds of chronologies (Standard chronology, STD,Residual chronology, RES, and ARSTAN chronology, ARS) of two sites were developed respectively. The regional climate data developed by using the arithmetical average of climatic data from 9 meteorological stations record the monthly mean temperature and precipitation near the sampling sites. Correlation analysis shows that the radial growth from two sites negatively correlate to the spring and summer temperatures. Compared to the temperature, precipitation has more significant effects on the pine's radial growth. Specifically, tree ring from Qianshan has positive correlations with precipitation in February, May (p<0. 05),and in April (P < 0. 01). Tree ring from Lushan positively correlated to the precipitation in previous September and current February, May and July (p<0. 05),especially in current September (p<0. 01). The October-June precipitation since 1774 was reconstructed using Chinese pine tree rings to explore regional moisture variations in southern Liaohe river plain. The reconstruction can explain 39. 9% of the total variance of actual records. The reconstruction shows eleven persistent wet periods : 1774 ~1795, 1809 ~1810, 1822 ~ 1823, 1835 ~1850,1867~1874,1889 ~ 1894,1907 ~1914,1931 ~1956, 1973 ~1976,1985 ~ 1991,and 2006 ~ 2010,and ten persistent dry periods: 1796~1808, 1811 ~1821, 1824 ~1834,1851 ~ 1866, 1875 ~1888,1895 ~ 1906, 1915 ~1930,1957 ~1972, 1977 ~ 1984, and 1992 ~ 2005,during the past 240 years. The wettest year is 1788, and the driest year is 1859. The variation of the reconstructed precipitation is mainly at high frequency level, and its cycles at ca.2. 0~2. 2-year, 2. 4-year, 3. 1 ~3. 2-year, and 3. 7 ~3. 8-year are significant (p<0. 05), of which ca.2. 1-year and 2. 4-year reach a extremely significant level (P< 0. 01). Also, the reconstruction has ca.50 ~70-year cycles (p<0. 05). The October-June precipitation is influenced by the East Asian monsoon. The strong East Asian winter monsoon or the weak East Asian summer monsoon indicates less regional precipitation, and the weak East Asian winter monsoon or the strong East Asian summer monsoon suggests more regional precipitation.