The user program of J-PARC/MLF is overviewed. Since MLF will be one of the major neutron facilities in the world, an international standard system for the user program is expected. It is also expected to establish a system to promote users from industries. The MLF user program is based on the IUPAP recommendation on the selection of proposals. Both open and closed accesses, biannual, regular, rapid accesses, etc. will be provided. All the features in the system are being introduced to maximize both scientific and engineering outputs from MLF.