In this paper, a wideband bow-tie slot antenna that couples to an extended hemispherical lens to realize high directivity, is proposed. The design consists of a conventional bow-tie with a tuning stub, which yields input impedance of 50 Ω over broad operating bandwidth. The antenna is designed for 60–110 GHz by using 3-D finite-difference time-domain (FDTD) method and 55% bandwidth is achieved for 10 dB return loss. The gain from the integrated lens antenna is 13.5 dB with half power beamwidth (HPBW) of ±12°. The measured return loss and radiation pattern agree very well with the theoretical predictions.