Some electric materials such as carbon or graphite powder were added to urea-formaldehyde resin to make plywood to study its electromagnetic shielding effectiveness （ESE）. Results showed that the smaller the granularity that the electric element was, the better ESE the plywood exhibited. The highest ESE value attained was 22 dB. However, the authors proposed that the mechanism and quantified relation between the ESE of composite plywood and the addition of electric material should be further researched.