In this paper, a compact printed monopole antenna with a coupled line and loop structure is proposed for GSM/UMTS/LTE and UWB in mobile application. This antenna has a monopole feeding which couples to a microstrip line and loop structures. It supports 1.7∼2.7GHz for GSM1800, GSM1900, UMTS, LTE and 3.1∼10.6 GHz for UWB. The proposed antenna has two structures which are coupled from monopole. One is a shorted microstrip line for a resonance of low frequency band and the other one is a loop structure for enhancement of bandwidth. With GSM/UMTS/LTE and UWB operation achieved, the proposed antenna only occupies a small space of 29 × 8 mm2 physical size. CST simulation was utilized in the design stage. The antenna was constructed on a substrate, FR-4, with the thickness of 0.8mm and relative permittivity of 4.3. The size of the substrate is 58 × 110 mm2.