Haikou is one of the most important ecological tourist city in China, even throughout the World. The ecological environment and climate is the most precious natural resources. Carrying out the research of climate change characteristics in Haikou could be used to enhance its ability to adapt to the long-term effects of climate change, and delay or avoid the threats caused by climate change to regional ecological security. This paper used the data of monthly mean temperature, precipitation and sunshine duration during the period from 1951 -2010 observed by national benchmark climate station and combined with some mathematical statistics methods such as linear regression method, Mann-Kendall nonparametric test, moving T-test, cumulative anomaly method and Morlet wavelet to analyze climate change characteristics in Haikou City. The results indicated that the climate change presented increasing annual mean temperature, decreasing annual sunshine duration, and climate tendency rate was 0.18 ℃/(10 a) and -83.1 h/(10 a) at the significance level alpha=0.01 respectively, the increasing rate of annual mean temperature was distinctly lower than that in whole China, and decreasing rate of annual sunshine duration significantly higher than in whole China. Moreover, no significant long -term change was observed in annual precipitation in the past 60 a. The stable period of climate changed significantly appeared in 1990s, mainly showed that increasing annual mean temperature and annual precipitation, decreasing annual sunshine duration, and fluctuations in climate change became the strongest since 2000 years. This indicated that the frequency and intensity of extreme weather events such as heat damage, floods and droughts will increase in the near future. In addition, the increasing rate of temperature in dry season was significantly higher than that in rainy season, but the change rate of precipitation was more obvious in rainy season than that in dry season. In addition, the fluctuation of climatic elements was more obvious in dry season than that in rainy season. The study of abrupt climate change and Morlet wavelet revealed that 1986 was an abrupt change point of annual mean temperature increasing, 1976 was an abrupt change point of annual precipitation reduction, 1993 was an abrupt change point of annual sunshine duration reduction, 1967~1978 and 1998~2010 correspond to cold period and warm period in Haikou respectively. Annual mean temperature and annual precipitation of Haikou existed evident characteristic time scale with 5-10 a, the periodic oscillation of annual sunshine duration were in 5-8 and 25-28 a.