Abstract: Northeast China is located in high latitudes,spring frost weather occurs frequently,which poses a serious threat to agricultural production.To clarify the characteristics of spring frost events in northeast China and provide reliable predictor is very important.Taking Liaoning province as an example,based on the meteorological observation data and meteorological reanalysis data in recent 60years,the late spring frost index（LSFI） in Liaoning province is defined,the relationship with the temporal characteristics of LSFI and the related large-scale circulation and the sea surface temperature（SST）is investigated.The results show that:LSFI has an interdecadal variation with a period of 14.25 a.The interdecadal enhancement is corresponding to a “Silk Road”pattern at middle latitudes,with anomalous cyclones over northeast Asia,which is beneficial to the transport of cold air.Meanwhile,there is a strong cyclonic anomaly over the Okhotsk Sea,which makes the cold air invaded at high latitudes affecting Liaoning province.And the southerly subtropical high is disadvantage to warm and humid air to north.In addition.SST also has important effects on late spring frost events.And there is a shift between the interdecadal variation of LSFI and SST around 1997.Before 1997,it is significant correlated with the North Atlantic “+-+ ”triple mode of SST in the early spring（March and April）.The wave energy originates from the North Atlantic converged in northeast Asia,which strengthens the cyclone anomaly.After 1997,it is positively correlated with the Pacific Decadal Oscillation（PDO）in the previous winter.The wave activity flux mainly originates from the Pacific Ocean and spreads eastward to northeast Asia via the North Atlantic.