In order to study the safety protection issues and explosion characteristics of colloidal charge structure under high temperature environment， the charge structure consisting of a thermally insulating outer layer， an endothermic colloid and an emulsion explosive was designed. The effects of three colloid proportions and two sensitizing modes （emulsion explosives were sensitized by sodium nitrite and expanded perlite respectively） of explosive in the charge structure on thermal insulation and explosion performance were studied by physical property measurement， thermometric analysis， explosion testing technology （underwater explosion， detonation velocity experiment， near-field detonation pressure measurement） and field experiment （sympathetic detonation， blasthole blasting）. The results show that the colloidal material containing 0.5% high molecular water-absorbent resin is suitable for the charge structure， attributing to the fire resistance， high specific heat and low thermal conductivity， which extends the thermally insulating protection time to 55 min. In underwater explosion and detonation velocity experiments， as the heating time of 100 ℃ water bath increases， all detonation parameters （peak shock wave pressure， specific impulse， detonation velocity， and total explosive energy） of the charge of two sensitizing modes decrease. Affected by the demulsification of emulsion explosive and the reduction of sensitization hot spots， the detonation performance of emulsion explosive sensitized by sodium nitrite （EE-SN） is attenuated greater than that of emulsion explosive sensitized by expanded perlite （EE-EP）. After heating for 2 hours， the total explosive energy loss of EE-EP and EE-SN is 4.76% and 17.62%， respectively. In the near-field explosion pressure measurement of colloidal medium， the colloidal layer in charge structure will weaken the strength of explosion shock wave. However， the blasting effect is good in the field experiment， and the charge structure has realized the 30 mm sympathetic detonation and the stable detonation propagation in the blast hole， indicating that the colloidal charge structure has a good application prospect for high-temperature blasting.