This paper presents the design of tri-band planar dipole antenna for PCS and WLAN services. A modification is made in the previously presented dipole antenna design [1]. The configuration of the proposed dipole antenna is given in Figure 1(a). The antenna design consists of a printed dipole and two parasitic elements which are behaving as resonators by coupling from the driving element. The proposed antenna is fed by using a balun which consists of a microstrip line with a radial stub [1]. From simulation, the resonant frequencies noted are 1.825 GHz, 2.54 GHz, and 5.20 GHz having impedance bandwidths 296 MHz, 139 MHz, and 130MHz for return loss less than −10 dB as shown in Figure 1(b). The gains at the resonant frequencies are 1.3, 2.26, and 1.8 dBi, respectively.