The active AP configuration algorithm has been proposed to optimize the configuration of the elastic WLAN system that dynamically changes the topology depending on traffic demands and environments. The multiple-input multiple-output (MIMO) is the technology to enhance the transmission capacity by adopting multiple antennas. It is common for access-points (APs) but is still rare for hosts. Thus, the location optimization for MIMO hosts in the field appears to be a contributing factor in improving the performance. In this paper, we study the MIMO host location optimization as an extension of the active AP configuration algorithm. The concurrent communications of multiple hosts with a single AP offer different throughput features from the single communication, which is considered. The effectiveness is verified through simulations and simple testbeds.