The work aims to explore the design scheme of the thickness of the thermal insulation layer of the storage containers to meet the technical requirements on the thermal insulation function of the storage containers. Based on the polyurethane heat preservation materials of low heat conductivity coefficient and according to Fourier's law and theoretical analysis of safety factor, the storage container’s thickness of the insulation layer was determined. Then high and low temperature tests for verification were carried out on the storage containers in accordance with the laboratory equipment environmental test method (GJB 150.4.A—2009). In the high and low temperature test, the monitoring results of the internal sensor of the storage containers were as follows:when the temperature was 22.2 ℃ in the containers and 40 ℃ outside the containers, the maximum temperature in the containers could reach 29.2 ℃ after 4 h; when the temperature I was 25.5 ℃ in the containers and −30 ℃ outside the containers, the lowest temperature in the containers was as low as 2 ℃ after 4 h; through analysis, the relationship between the internal temperature of the containers and the time and the temperature difference of the containers was:when the temperature of the outside of the containers was raised by 1 ℃, the rate of temperature rise inside the containers was 0.037-0.1 ℃/h; when the external temperature of the cabinet was reduced by 1 ℃, the cooling rate was 0.07-0.094 ℃/h. The designing scheme proposed meets the technical requirements on thermal insulation function of the storage containers.