This study presents a bilayer polydimethylsiloxane (PDMS) composite microwave absorber, consisting of Fe2O3 and polytetrafluoroethylene (PTFE) fillers, to enhance the functioning of radio frequency identification (RFID) systems on conductive surfaces. The uniform Fe2O3/PDMS and PTFE/PDMS composites are prepared by mixing PDMS and respective filler through a desktop three-axis roller machine followed by curing at 80 °C for two hours. The composites are then joined to create a bilayer composite mat. The combination of a 70 wt% Fe2O3/PDMS composite with a 50 wt% PTFE/PDMS composite demonstrates the best performance. The Fe2O3/PDMS composite shows the high reflection loss of 47.98 dB and a total shielding of 4.1 dB, while the PTFE/PDMS composite exhibits the reflection loss of 47.0 dB and a total shielding of 0.6 dB. The optimized bilayer composite enables a tag recovery of approximately 87.57 %. These findings demonstrate its practical application in reducing interference and enhancing the RFID tag detection.