Zeolite FAU was heated directly by microwave irradiation at 2450 MHz in an open system without special loading materials. It was discovered that zeolite X was heated to 1473 K about 90 seconds at power output of 400 W. HY type zeolite was also heated to 1373 K although it needed relative long time (about 11 minutes). Influences of exchangeable cations and adsorbed substances on zeoliteu001fs ability to absorb microwaves were also discussed. Zeolite FAU was heated directly by microwave irradiation at 2450 MHz in an open system without special loading materials. It was discovered that zeolite X was heated to 1473 K about 90 seconds at power output of 400 W. HY type zeolite was also heated to 1373 K although it needed relative long time (about 11 minutes). Influences of exchangeable cations and adsorbed substances on zeolite u001fs ability to absorb microwaves were also discussed.