【Objective】Litchi (Litchi chinensis Sonn.) is a typical subtropical fruit tree and requires plenty heat and precipitation for survival and growth. With the impact of climate change, the area suitable for cultivation of litchi will expand, and the risk of cold and heat injuries may increase. Recently, some litchi cultivation areas in China have proved to be unsuitable for litchi cultivation. However, the reason is not clear. So, it is important to reveal the relationships between the distribution of litchi and climatic factors and to determine the key climatic factors affecting the distribution of litchi in order to correctly understand the impacts of climate change on the distribution of the species in the future and to regionalize litchi cultivation based on climate conditions. The aim of the paper is to analyze the relationships between the distribution of litchi and climatic factors and to identify key climatic factors affecting litchi distribution in China. 【Methods】Climatic data from 1971 to 2000 were provided by the National Meteorological Information Center, China Meteorological Administration, and 38 climatic indexes calculated using Fortran software were used to reveal the relationship between the distributions of litchi and climatic factors. The distributions of litchi were mainly determined based on distribution records or data from litchi literatures, such as Chinese Fruit-Litchi, the Academic Fruit Cultivation Theory, Litchi in Guangdong, Litchi in Guangxi, the Tropical and South Subtropical Fruit Trees in China, Crops and Their Wild Relatives Plants In China-Fruit Tree, and the Litchi. In addition, some records or data of distribution of litchi were collected from full-text database of the CNKI China periodical and SDOS full-text electronic journals (Elsevier full-text electronic journals). The geo-referencing methods based on an index of the Atlas of the Peoples Republic of China, and ArcGIS 9.3 software was used to draw the distributions of litchi. The relationships between the distribution of litchi in China and climatic factors were analyzed by using the ArcGIS 9.3 software, and the principal component analysis in SPSS software was used to identify the key climatic factors affecting the distribution of litchi in China.【Results】The results showed that wild litchi scatters in a narrow area, while the cultivated litchi is distributed in a broader area in south China. The wild litchi is adapted to a climate with a mean annual temperature of 22.32 ℃, a lowest temperature of 1.33 ℃, the mean temperature in January of 15.16 ℃, the mean temperature in winter of 17.10 ℃, ≥10 ℃ accumulated temperature of 8 120.57 ℃, an annual precipitation of 1 665.17 mm, the precipitation in summer of 701.53 mm, the precipitation in autumn of 629.53 mm, the Thornthwaite humidity index of 9.41, and the Holdridge annual bio-temperature of 21.98 ℃. As for cultivated litchi, the suitable mean annual temperature is 20.61 ℃, and the lowest temperature -0.94 ℃, the temperature in January 12.14 ℃, the temperature in winter 17.10 ℃, and ≥10 ℃ accumulated temperature 7 429.71 ℃, annual precipitation 1 573.51 mm, the precipitation in summer 690.36 mm, the precipitation in autumn 455.45 mm, the Thornthwaite humidity index 9.85, and the Holdridge annual bio-temperature 20.39 ℃.