Electromagnetic shielding effectiveness (SE) of textile and various composite materials should be measured since their SE values cannot be calculated as in the conventional metal plate. Coaxial Holder Method is a measurement method that SE of textile materials is tested in the controlled test area. This measurement method has several shortcomings such as limited frequency range and impractical test conditions. In this study, firstly a new test apparatus was developed with an aim to overcome limitations of ASTM D 4935. Then, SE values of hybrid fabrics produced under the controlled conditions were tested with this new test apparatus and the test results compared with SE results obtained from ASTM D 4935 method.