The Middle Yanshan region in the north of the Hebei province is rich in geothermal resources. However, the absence of research on the terrestrial heat flow and lithosphere thermal structure seriously restricts the exploitation and utilization of thermal resources. This paper studies the physical parameters and heat flow in the shallow and deep rocks encompassing the Qijia- Maojingba geothermal field. Based on this data a conceptual lithospheric thermal structure model is established and information on heat flow is obtained. It is found that there is a good correlation between terrestrial heat flow (an average of about 57 mW/m2) and the temperature of the surrounding hot springs in the middle Yanshan Region. The terrestrial heat flow in the Qijia- Maojingba area is about 74. 9 mW/m2, which is the highest in the Yanshan Region. With the one- dimentional steady state thermal conduction formula, the temperature at different depths is calculated in the Qijia- Maojingba geothermal field. The depth of Curie surface is about 21. 5~22. 8 km with a temperature of 570~600 ℃, and the Moho temperature of about 815 ℃. Most of the analysis results presented above are consistent with previous research findings in the research area and its vicinity, confirming the reliability of the lithospheric thermal structure model established in this study.