Applying the monthly precipitation data of 22 stations in Liaoning Province from 1956 to 2011, the grads and years of droughts and floods were determined by Z index. Characteristics of droughts and floods nearby the sunspot extreme years were analyzed by frequency analysis method. Morlet wavelet analysis was made to analyze the changes of the Z index and sunspot. Results show that: (1) The frequency of droughts and floods was the same in the province in the past 56 years. The overall trend was from flood to dry, especially when entering in the 21 century. The drought frequency increased significantly, showing a drought phenomenon. (2) The sunspot number and the drought and flood phenomenon in Liaoning Province showed a negative relationship. The area appeared to be a drought year in sunspot peak and a flood year in sunspot valley. (3) There was a relationship between the drought and flood cycle and sunspot cycle in 7~11 years, and the change of sunspot number influenced the droughts and floods in Liaoning Province. In the next few years, sunspots will be near the active period and precipitation will decrease correspondingly.