Based on the observed precipitation data from 394 stations over Qinling and surrounding areas, the ERA-Interim reanalysis data from the European Centre for Medium-range Weather Forecasts( ECMWF), the Empirical Orthogonal Function( EOF),wavelet and regression analysis methods, the major modes of summer precipitation in Qinling and surrounding areas and their associated atmospheric circulation anomalies are analyzed.Results show that: ( 1) The first four EOF modes account for 73% of the total variance and the principal component has significant interannual variability with 24 years period.EOF1 reflects the difference climate change between south and north Qinling.EOF2 reflects the reverse phase oscillation on both sides of the loess plateau.EOF3 is characterized by opposite distribution between southwest and northeast Qinling.EOF4 reflects Guanzhong plain topography precipitation contribution.The EOF3 and EOF4 also have 48 years interannual variations.( 2) Regression analysis showed that when EOF1 in positive phase,200 hPa Jet is weak,at the same time,midlatitude trough and West Pacific subtropical high are weak,anomalous water vapor transport from East China Sea favors more precipitation in northern Qinling.EOF2 and EOF3 have significant Mongolia low and Northeast cold vortex circulation characteristics respectively.500 hPa circulation anomaly of EOF4 was not significant.( 3) A summer monsoon index in Qinling is defined, the monsoon index of the regression field is significantly related to the time coefficient of the precipitation spatial mode,more( less) precipitation in Northern Qinling, less( more) rainfall in the South, reflecting the strong( weak) monsoon year conversion.Otherwise, in different strong( weak) monsoon years, the atmosphere circulation in Qinling has big difference,which can trigger a variety of precipitation mode and phase oscillations.