^99mTc is the most commonly used medical radionuclide for imaging in nuclear medicine. The use of accelerators for the production of ⁹⁹Mo is an alternative to nuclear reactors. To generate a neutron source for radioisotope production, a plan of moderating, the proton induced neutrons, is proposed. Fast neutrons were generated by a suitable target under proton beam bombardment from a low-energy and low-current small cyclotron and simulated by Monte Carlo method.