Broadband, high resolution millimeter-wave imaging radar using inline transmitting (Tx) and receiving (Rx) antennas is proposed. The imaging radar is composed of dielectric aspheric lens and inline Tx/Rx antennas located both in the axis of lens. As Tx/Rx antennas, antipodal Fermi antenna is employed. Basic characteristics of the proposed imaging radar including the effect of offset of Tx/Rx antennas is discussed by using FDTD analysis and experiments, in which high isolation between Tx/Rx antennas is obtained. Imaging of three objects is performed using frequency range of 35 GHz to 70 GHz showing high resolution less than 8 mm and clear image.