Abstract: The influences of 11 El Niño and 8 La Niña events since 1961 on winter temperature variation in Yunnan have been analyzed. It is found that the winter temperature in Yunnan is higher (lower) in El Niño (La Niña) years, which has warm (cold) winter feature, and is more obvious in eastern, middle and southern Yunnan. The sea surface temperature a nomaly (SSTA) over the equatorial East Pacific has the positive significant correlation with winter temperature a nomaly in Yunnan, and monthly SSTA in the previous year has better positive correlation with temperature anomaly of Yunnan in January of the next year. The SST positive (negative) anomaly is a strong signal of warm (cold) winter in Yunnan. Under the influence of ENSO, the weak (strong) winter monsoon over East Asia is the main cause of warm (cold) winter in Yunnan.