The concept of layer-structured radome design is proposed and explored for millimeter-wave wireless communications, which uses only one medium comprising of three different structured layers to mimic the conventional sandwich structured radome with multiple media so as to achieve broadband, low-reflection, and low-loss properties. The analytical model of the layer-structured radome is given for the optimal design, and full-wave simulations are adopted to examine the radome performance with either normal or oblique incidences. Three designed cases are obtained with/without considering the fabrication tolerance, and their simulation results show that the demanded broadband (>34%) and low-loss performance has been well achieved in the 28 GHz band for the 5 th generation (5G) wireless communications.