[en] Booster Synchrotron Utilization Facility under construction has been completed in the most part in this spring. The first proton beam from KEK Booster Synchrotron was delivered to the new facility on June 18. The facility has been into operation on schedule. In this report, the beam line, experimental facilities of puised neutron source and meson physics in Booster Synchrotron Utilization Facility are described and the present status of the facility is also given. (author)