Microwave imaging has become a hot topic in the area of microwave engineering. In this paper, we propose a new approach for microwave imaging based on multiple transmit and receive antennas assisted with compressed sensing at single frequency. Different from compression achieved by frequency diversity relay on a wide bandwidth, compressed sensing is applied to figure out the location and shape of unknown target utilizing the spatially diversity of antennas' location. Thanks to the compressed sensing, inversion results can be obtained with much faster data processing than traditional methods. Numerical simulation of single target as well as multiple targets is investigated, and the results demonstrate the effectiveness of the proposed approach. With the simple implementation for fast imaging, our method can be potentially used in practical applications of microwave imaging.