A novel compact coplanar waveguide (CPW)-fed planar monopole antenna with triple-band operation is presented for simultaneously satisfying the LTE 2600, WiMAX, WLAN and X-band applications. It is printed on a single-layered FR4 substrate. In this paper, the proposed antenna, which occupies a small volume of 30×28×0.8mm3 including the ground plane, is simply composed of a CPW-fed monopole with U-, L- and T-shaped slots. By carefully selecting the lengths and positions of both L-shaped and U-shaped slots, a good dual notched band characteristic at center-rejected frequencies of 3.10GHz and 4.50GHz can be achieved, respectively. The T-shaped slot is etched on the radiating element to excite a resonant frequency in the 7GHz band. Then, to prove the validation of the typical design, a prototype model is fabricated and measured. The experimental result shows that the three frequency bands of 2.31-2.80GHz (490MHz), 3.37-3.84GHz (470MHz) and 5.04-7.94GHz (2900MHz) can successfully cover the desired bandwidths of LTE2600/WiMAX (3.50/5.50GHz)/WLAN (5.20/5.80GHz) and the X-band communication systems (7.1-GHz operation). The principal applications of the X-band are radar, aircraft, spacecraft and mobile or satellite communication system. Nearly omnidirectional and bidirectional radiation patterns of the triband antenna are observed in both H- and E-planes, respectively. In addition, a reasonable gain over the operating bands has been obtained. Indeed, the good agreements between simulation and measurement results have validated the proposed structure, confirming its potential for multiband wireless communication services.