Based on the monthly meteorological data of 29 stations in Yunnan Province druing 1958-2011, after defining the level and years of droughts and floods by Z index, the influence of sunspot activity and ENSO(El-Nino-La-Nina) events on droughts and floods was analyzed by using frequency analysis and Morlet wavelet method. The results showed that:(1) In recent 54 years, the precipitation in Yunnan Province was decreasing with the speed of 4.505 mm/10 a, and the occurrence of drought and flood disasters was increased, and drought frequency was significantly higher than that of flood since the 21st Century.(2) The drought and flood disasters and the sunspot number were negatively correlated in 1960-1989 except 1967-1972, and turn to positively correlated after 1990; the sunspots decreasing trend was the same as drought trend.(3) There was a 14 years cycle corelation between ENSO events and drought and flood disasters in Yunnan Province. The drought disasters increased with the El-Nino intensity increase, and the flood disasters increased with the La-Nina intensity increase.