In this paper, a novel miniaturized planar antipodal Vivaldi antenna (AVA) with high gain and back radiation reduction for 5G millimeter‐wave (mm‐Wave) communication is presented. First, due to the use of the gradual corrugated edges (GCE), the operating band of the antenna is extended in the direction of lower frequencies and the overall gain is also improved as well. Second, its gain of the antenna is better enhanced at the high frequency band through I‐Shape Metal Director (IMD). Lastly, to further reduce the back radiation, the split ring resonance branches (SRB) are added to the ground. The antenna front‐back ratio has improved considerably to over 20 dB. Meanwhile the antenna gain is improved further. Furthermore, a prototype antenna array was fabricated and the measurement results clearly show that the antenna array gain varies in the range of 15.86–16.43 dB when operating in the 5G millimeter wave band (24.75–28.35 GHz). [ABSTRACT FROM AUTHOR]