The fiber-optical coil is an important part of fiber-optic guidance weapon system.Due to the difference of the coefficient of thermal expansion(CTE) between the different composition materials,the performance of the accurate winding fiber- optic coil will be significant changed by the temperature.It is necessary to research the temperature matching performance of the fiber-optic coil,in order to ensure the structural stability and performance reliability.This paper presents a system to test the CTE by the double CCD camera,which is a non-contact test method.It uses the double light patch imaging amplification and sampling technology and gets the sample′s axial inflation volume in a temperature range by using the image processing method.In the paper,the test and analysis of the CTE of the off-spool fiber-optic coil,carbon fiber mandrel,polytetrafluoroethylene (PTFE) adjustment layer and the complete fiber-optic coil are finished by using the system.The results are the same in the theoretical analysis and the experiment,which proves that this test system is correct and feasible.