[en] In this study, the major basis of Mo- production using irradiation method for targets of enriched uranium is presented. Factors such as neutron flux, time of irradiation, and enrichment ration have also been analyzed. It was concluded that Mo-production requires nuclear reactors having high neutron fluxes, and that raising the neutron flux results in increasing the Mo-activities especially at fluxes that are higher than 10¹⁴n.cm^-2.s^-1. Time of irradiation was found to have adverse i.e. positive and negative effects on Mo activity. Therefore, the optimum irradiation time should be determined. The Mo-production was modeled through a set of differential equation with respect to time with aim to study the most influencing factors on Mo production, especially the effects of neutron flux and time of irradiation. In addition, the mass of plutonium produced during the irradiation of low enriched uranium has been evaluated. An investigation as to whether ⁹⁹Mo could be produced in the Syrian MNSR has been made. The result shows that a specific activity of 0.3773 Ci/g for ⁹⁹Mo could be produced. In future, a nuclear research reactor having neutron flux of 10¹⁴n.cm^-2.s^-1 and 8 irradiation sites suitable for targets of 5 g of ²³⁵U could produce about 5000 Ci on a weekly. Calculation and simulation have been achieved using the already developed DARE-P simulation language which was modified and improved in the nuclear Engineering Department in the Atomic Energy Commission of Syria. (author)