Based on the NCEP/NCAR reanalysis data and ECMWF reanalysis dataset from 1981 to 2017, the impacts of the winter cold air over high-latitude areas in North America on the summer precipitation anomaly over South America are studied. The results show that the winter cold air over high-latitude areas in North America influences the location and intensity of the intertropical convergence zone (ITCZ) by influencing the intensity of the southward cross-equatorial flow, which further affects the change of weather in South America. The southward intrusion of winter cold air over North America can significantly strengthen the southward crossequatorial flow in the area between 80°W and 70°W, resulting in the abnormally southward and strong ITCZ in South America in 2011, which is an important factor of the abnormally more precipitation. The correlation analysis shows that the winter cold air over North America has more significant influence on the location of ITCZ in South America.