Millimeter-wave （MMW） imaging is of interest as it has played an essential role in personal surveillance. The existing MMW short-range imaging mechanisms in personal surveillance can be mainly divided into SISO and MIMO. The SISO mechanism can achieve fast and accurate imaging. However， as the operating frequency increases， the number of antennas required increases rapidly， and the antenna spacing decreases， which not only causes an increase in system cost， but also makes it difficult to suppress antenna coupling. Although the MIMO mechanism reduces the number of antennas required for imaging and increases the antenna spacing， it is currently unable to achieve rapid and accurate reconstruction comparable to the SISO mechanism. In this paper， a MIMO short-range imaging mechanism has been proposed， which is well-suitable for fast and accurate reconstruction， and the applicable conditions of the mechanism were given quantitatively. Unlike the traditional MIMO short-range imaging mechanism， the proposed MIMO imaging mechanism satisfies the principle of equivalent phase center （EPC） in short-range imaging by ingeniously designing MIMO sub-arrays. Therefore， it can directly use various accurate and fast imaging algorithms developed for SISO mechanism to reconstruct images， such as range migration algorithm （RMA）. It means that the algorithm has the advantages of both SISO mechanism and MIMO mechanism. The demonstrations in E-band show that the proposed MIMO mechanism exhibits the same level of imaging quality and reconstruction speed as SISO mechanism in short-range imaging， but the antenna utilization rate and the antenna spacing can be increased by more than 4 times. When compared with the traditional MIMO imaging mechanism， the proposed MIMO mechanism not only has better imaging quality but also greatly improves the reconstruction speed， which is nearly 200，000 times faster than the traditional MIMO mechanism in a typical imaging scene of 1m×1m×0.2m volume with a voxel size of 1.85 mm3 . Both simulation and experimental results verify the effectiveness of the proposed MIMO mechanism.