This paper presents circular-shape monopole antenna for wireless body area net- work (WBAN) applications at 3.1 to 5.1 GHz and 6.5 to 8 GHz. The design and simulation of proposed antenna for WBAN applications in the free space and close proximity of body surface has been done by using CST Microwave Studio. The proposed antenna was designed on FR4 substrate with dielectric constant (εr ) of 4.4 and thickness of 1.6 mm. The final optimized de- sign is 50 × 40 mm2 . The simulated current distribution on the radiating patch for the proposed circular-shaped monopole antenna frequencies of 3.3 and 7.5 GHz in the free space is presented. The size of circular-shape monopole antenna it is suitable for WBAN application.