Abstract:Climate and energy has an increasingly close relationship and degree day is the simplest and the most reliable index to measure energy demand. Spatial and temporal distribution characteristics of heating and cooling degree days, based on Mann Kendall test, by selecting a set of daily average temperature data in Shandong Province, have been analyzed in this paper. Also, urban heat island effect has been discussed by means of the trend of degree days in Jinan. Results show as follows: （1) Spatial distribution of heating degree days is mainly affected by latitude and topography, average value fluctuating in a range of 2279-2945 ℃·d, while distribution of cooling degree days tends to be related to topography and land sea distribution, average value varying between 1 and 155℃·d. （2) Heating degree days appear to be significant decreasing trends varying between 44.6 and 162.3 ℃·d·（10 a）-1, while cooling degree days at 18 stations present significant increasing trends, ranging between 4.5 and 17.3℃·d·（10 a）-1, no remarkable positive trends observed at the other stations. （3) Heating degree days in the suburb of Jinan are always higher than those in the urban during the period from 1965 to 2010, on the contrary, cooling degree days in the urban are higher in most years of the period. The difference value of heating degree days and cooling degree days between in the urban and in the suburb indicates the highest level in the late 1970s and in the early 1980s and the lowest level in recent years.