According to the meteorological data in Lijiang from 1954 to 2009, the main tourism climate factors are analyzed, including air temperature, precipitation, relative humidity, wind speed and sunshine hours. A new comprehensive comfort index is developed based on the calculation of THI, K and ICL. This new index has some peculiarity like comparable, able to add together and so on. The climate comfortable degree of Lijiang is analyzed by the new index, and the grades of fitness and spatial distribution are divided. The following conclusions can be drawn: 1) The suitable traveling period of Lijiang is from March to November, and the best period is from May to September; 2) Since 2000, the air temperature has risen, wind speed has decreased, precipitation has reduced, humidity has decreased, with a warming-drying trend, which will attract more visitors and will increase human comfort during the trip; 3) The suitable travel duration will extend. The Lijiang tourism will be developed well.