Polyethylene film having thermal insulation layer, and high-altitude balloon

A polyethylene film having a thermal insulation layer, comprising: a solder layer (1); a load bearing layer (2), located on the solder layer (1); a barrier layer (3), located on the load bearing layer (2); a thermal insulation layer (4), located on the barrier layer (3); and a weather-resistant layer (5), located on the thermal insulation layer (4). According to the polyethylene film, a thermal insulation layer containing metal particles is additionally provided, and by means of scattering and blocking effects of the added metal particles, most light is diffuse-reflected or blocked after incident light passes through the processed film; thus, the occurrence of increase in temperature of the material is effectively avoided, and the temperature difference in a balloon is reduced. The film can be used for a high-altitude balloon.