Abstract: The high demand for faster and more reliable services in several applications of modern communications increases the requirements for a large data transmission capacity and hence a wide operational bandwidth. In addition to that, mobile communication set some strict specifications concerning the size, the weight and the efficiency of the RF front-ends, which are responsible for the transformation of the base-band signal to a radiated electromagnetic wave and vice versa. The element of the RF front-end, mainly determines the size and the efficiency of the antenna. In this paper, dual-frequency is obtained, using cylindrical dielectric resonator antenna with a parasitic c-slot fed by a microstrip line. The structure consists of two radiating resonators that are tightly stacked together and resonate at different frequencies. The first frequency is from the DRA and the other from the c-slot. The use of dielectric resonator in feeding circuit requires accurate knowledge of the coupling between the resonator and circuit. So, in order to match the dielectric resonator to the feedline and to excite the HEM11δ mode in the resonator, the most common method of feeding technique used is aperture-coupled arrangement. The proposed DRA is suitable to be mounted above the system circuit board of the mobile communication devices, and is very suitable for application in mobile communication systems.