A wide-beamwidth magnetoelectric (ME) dipole antenna for millimeter-wave (mm-wave) phased array applications is proposed in this letter. The antenna is fed by a substrate integrated waveguide. The electric dipole is formed by two patches, while the magnetic dipole consists of two apertures between the two patches. A short strip is introduced to connect the two patches, which can improve the impedance matching performance. The impedance bandwidth with | <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</sub> | < −10 dB for the antenna element is 19.9% (28.11–34.32 GHz), as shown in the simulated results. And its half-power beamwidth in the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">xoz</i> plane and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">yoz</i> plane is wider than 82.1° and 81.8° over the operating band. To test the scanning potential of the ME-dipole antenna, a 4 × 4 phased array is constructed in high-frequency simulation software. The simulated scanning range of the phased array is beyond −41°∼41° at two sampling frequencies. Besides, a 4 × 4 antenna array is designed, processed, and measured. The array demonstrates a −10 dB fractional bandwidth of 15.3% (27.7–32.3 GHz) with a peak gain of 17.79 dBi at 30.4 GHz. The proposed ME-dipole antenna demonstrates good potential for 5G mm-wave phased array applications.