A layered-printed RFID antenna idea and layered butterfly antenna model were put forward for RFID printing. Simulations were carried out and the influence of ink thickness on radiation efficiency of butterfly antenna was studied. Simulation results showed that the current density in different area has influence on radiation efficiency; there is a best point on the antenna which can improve the radiation efficiency of layered antenna higher than single-layer printed antenna. The problems of contradiction between ink thickness and radiation efficiency can be solved through optimization.