Abstract: Based on the 2009-2011 daily air temperature observation data from 11 automatic weather stations in the mountainous region of northern Guangdong, this paper calculated the heat factors in the region, including the beginning date of 10 ℃, the ending date of 15 ℃, the duration days of 10-15 ℃, the accumulated temperature above 10 ℃, the days of minimum temperature below 5 ℃, and the mean monthly temperature,  with the linear regression model of the heat factors and latitude established. In 2009-2011, the heat factors in the region had significant correlations with latitude, and the heat resource at the same latitudes differed apparently between south and north slopes. With the increase of latitude, the beginning date of 10 ℃ delayed, the ending date of 10 ℃ advanced, and the duration days of 10-15 ℃, the accumulated temperature above 10 ℃, the days of temperature above 10 ℃, and the mean annual air temperature decreased. The vertical variation rates of the heat factors were larger on south slope than on north slope. The results of this study could be used for fitting the vertical distribution of heat resource in the areas with no weather station, and provide basis for the fine regionalization of agricultural climate.