A triple-band low-profile planar antenna is developed for wireless applications. The triple-band planar antenna consists of a two-strip monopole for the 2-GHz band, a horizontal monopole for the 3.5-GHz band, and a vertical monopole for the 5-GHz. The planar antenna is printed on a very thin substrate (0.254 mm in thickness) with a very low profile (8 mm in height). The antenna achieves a bandwidth of ~35% at the 2-GHz band, ~10% at the 3.5 GHz, and ~15% at the 5-GHz band, which may find applications in wireless/mobile devices.