<p>A planar wideband quasi-Yagi antenna for vehicular application is proposed in this paper. The presented antenna composed of microstrip to slot line transition (MST), coplanar striplines, a driver diamond dipole, and seven parasitic elements. The diamond dipole is linked to the ground plane through coplanar strip lines. The bandwidth of the designed quasi-Yagi antenna is improved by using the diamond-shaped dipole when compared to a regular strip dipole. By adding symmetrical rounded stubs, the size of the ground reflector is increased to improve impedance bandwidth. Moreover, five parasitic elements are positioned above the two parasitic directors to enhance the end-fire radiation and the impedance matching. The measured impedance bandwidth of the proposed antenna is 128.46% (3.92-18) GHz and a peak gain of 9 dBi is obtained. The presented antenna is highly suitable for V2X communication and mobile broadband applications.</p>