Because of the difference of thermal physical properties between subsurface target and the soil, the temperature field distribution on the surface of the whole soil area is under its influence and the target is easily detected and destroyed by enemy. To solve this problem, taking into account the influence of solar radiation, sky radiation and wind speed, the heat transfer model of temperature distribution of the region containing buried target was established, which revealed the impact of buried target on the regional temperature field during different time. Based on the transformation thermodynamics, the thermal conductivity general expressions of spherical transient thermal cloak was derived by the means of coordinate transformation. According to the equivalent medium theory, the designed thermal physical parameters were homogenized and the feasible of target infrared stealth technology was verified based on the thermal cloak by numerical method.