The document describes the design of a compact printed antenna for UMTS and WiMAX applications. A rectangular microstrip patch antenna with two L-shaped slits is proposed to reduce the size by 73% compared to a conventional patch antenna. Simulation results show the antenna operates in three frequency bands with return losses of -16.37 dB at 2.03 GHz, -14.56 dB at 2.65 GHz, and -21.06 dB at 3.42 GHz and corresponding bandwidths of 15.02 MHz, 12.72 MHz, and 42.36 MHz respectively. Measured results agree reasonably well with simulations. The antenna achieves multiband operation and size reduction for wireless communication applications.