[en] Aim: ^117mSn has a half-life of 14.0 days, decays to stable ¹¹⁷Sn emitting a γ-ray of 159 keV, that can be used for obtaining in vivo images. It main use is in therapy, as a bone cancer therapeutical agent, due to the conversion electrons of 126.8 and 151.6 keV. The nuclear reactions that lead to the production of this isotope are: ¹¹⁷Sn (p, n) ¹¹⁷Sb→ ^117mSn, ¹¹⁸Sn (p, 2n) ¹¹⁷Sb → ^117mSn and ¹¹⁹Sn (p, 3n) ¹¹⁷Sb → ^117mSn. The objective of this work is to describe a production method of high specific activity ^117mSn. Materials and Methods: 1. Irradiation of natural tin in the CV-28 Cyclotron at IPEN-CNEN/SP. 2. Chemical separation of tin - antimony by an ion exchange technique. 3. Quality control of ^117mSn: chemical, radiochemical and radionuclidic impurities. Results: 1. The thick target yield for the production of ^117mSn was 0.784 MBq/□Ah. 2. The target was dissolved into concentrated HCl, hydrazine was then added for oxidizing and the solution taken to dryness. The solid was dissolved with concentrated HCl and the chemical separation was processed in an anion resin Dowex AG1-X8 (50 - 100 mesh). 3. The chemical levels of tin and antimony were 3 ppm and less than 2 ppm, respectively. Nearly 97% of ^117mSn was in the form of Sn⁺⁴. The radionuclidic impurity level of ¹¹³Sn and ^119mSn can be strongly reduced if the first chemical separation is performed 2 hours after the end of the bombardment and the decay time of ¹¹⁷Sb is reduced to 19 hours. Conclusions: A reliable production method of ^117mSn was developed through the irradiation of tin target