The refill-prescription system widely implemented overseas has been discussed toward its legislation for many years but has not been enforced yet in Japan. In considering introduction of such a refill-prescription system, numerical economic effects of its introduction can be expected in this paper. Based on the survey by Kurata at al. in 2016, the first and second groups were defined for patients with prescriptions of the same medicine more than twice for 14 days or more (20.2%) and for patients in the first group who were prescribed medication for more than 180 days and visited the pharmacy over 330 days (4.4%), respectively. The number of refill-prescriptions were estimated from the total number of the prescriptions put out in 2016. In the first group 166.7 million prescriptions were replaced by refill prescription, resulting in the reduction of medical and insurance expenses by 155.6 and 108.9 billion yens, respectively, while in the second group the reduction of 36.31 million prescriptions as well as 33.9 and 23.7 billion yens for those expenses, respectively, were expected. The monthly working time of overworking doctors with poor working environment was also calculated to be shortened by 6.1〜12.1 and 1.3〜2.6 hours for these two groups, respectively. Additionally, the introduction of the refill-prescription system was estimated to reduce the physical burden of one patient by 2.7〜5.3 hours per year for consultation and waiting hours in the medical institutions. Therefore, the refill-prescription system is thought to be useful for efficient allocation of medical resources to patients.