At present, the use of sun-shading system in China has developed rapidly. Requirements and calculation methods for sun-shading system were proposed in the current thermal design code for civil building and the design standards for energy efficiency. But thermal performance of these structures is still lack of testing and evaluation methods. Based on relevant engineerings and researches results from domestic and international, this paper has proposed test method for measuring the SHGC of sun-shading system using calibrated hot box. This paper has established a good foundation for further research on evaluation method for sun-shading system.