A printed apollonian gasket monopole antenna with CPW-feed is proposed for ultra-wideband applications.The Ultra-wide bandwidth of this antenna is achieved by modified the CPW ground plane. The experimental result of this antenna exhibits the ultra-wideband characteristics from 2.8 to 15 GHz at VSWR 2:1. The simulated results calculated from high frequency structure simulator are in good agreement with experimental results. The measured radiation patterns of this antenna are omnidirectional in H-plane and bidirectional in E-plane. The radar cross section (RCS) of this antenna is also studied for structural mode and antenna mode scattering. This type of antenna can be useful for a number of applications such as ultrawideband system, radar, ground penetrating radar, medical imaging, and other military applications. © 2012 Wiley Periodicals, Inc.