Abstract: In this paper 14 heat flow values obtained on geotherm and geotemperature measurements in Tangshan and its surroundings are described. They are in range from 1.11 to 2.53 HFU. The geothermal gradients are less than 2℃/100m for Tangshan and its surroundings, about 3.3℃/100m for Dagang, Tanggu and Bogezhuang, about 3.5℃/100m for Tianjin.Geothermal characteristics are closely related with the geotectonic features. To our knowledge, the heat flow values vary from 1.1 to 1.31 HFU for the Yanshan upris-ing area, they are 1.66-1.90 HFU for some fault zones and anticlinal axis. For the study region the geothermal gradient is less than 2℃/100m since they are located in the Yanshan fault block-depression. For the Huanghua depression, which acts as a Meso-Cenozoic subsidence region with thickness of Tertiary sediments about 6000m and shows a significant contrast with the Yanshan uprising area due to the vertical differential movement, the heat flow values vary from 1.86 to 2.53HFU, its geothermal gradient is larger than 3℃/100m. And within this depression the"ancient burried mountain" gives the heat flow values larger than 2.0 HFU, and the "depression" of second order yields this values about 1.86 HFU. For the junction of Huanghua depression and Cangzhou uplift these values are lower, as 1.22-1.51HFU.We have calculated the heat flow values and geotemperature for the Moho surface, for example, they are 0.33HFU with 532℃ in Tangshan; 0.99HFU with 956.6℃ in the Huanghua depression; 0.8 HFU with 883.4℃ in the southeastern part of Beijing; 0.45HFU with 676.8℃ in Yanqing County.It is suggested that the distribution of "hot region" and "cold region" are very important in studying the development of earthquakes from the geothermal point of view. Based on the geological structure, magmatism, calculated temperatures of earth' crust and upper mantle, data on magnetotelluric sounding, aeromagnetic survey and so on, it is proposed that the partial melting can be expected in the upper mantle beneath the northern Huanghua depression leading to high concentration of thermal stress and thus providing the driving force for the occurrence of the Tangshan earthquake.