Two thermal behavior experiments of light gauge steel-framed composite walls with slotted studs and with external thermal insulation layers were carried.The method of thermocouple temperature measurement was used.The heat transfer coefficients and the temperature of measured points of composite wall were deeply investigated and were compared with the FEA model results.Results show that web slotted studs can reduce the heat loss of light gauge steel-framed composite walls,thus weaken the thermal bridge effect of the location in stud part,then significantly improve the thermal insulation properties of composite walls.The composite wall heat transfer coefficient of the two test schemes are 0.315 W/(m2·K) and 0.250 W/(m2·K) respectively,which can meet the residential building envelope heat transfer coefficient limit value of cold areas.