[en] The Fricke dosimeter is the most used liquid chemical dosimeter. High dose rate (HDR) brachytherapy using 192Ir sources is an important treatment option and it has been shown to be a feasible option for the absorbed dose standard. One of the parameters used to determine the absorbed dose at the Fricke solution is the G-value. This parameter is crucial and can be defined as the number of molecules of Fe+3 produced per Joule of energy absorbed in the solution. Few authors have determined the G-value for energies below the 60Co. Most part of papers on the literature compare the G-value to 60Co and different beam qualities. The G-value for energies lower than Co-60 are not well defined, some authors obtained it through calorimetric measurements and others the G(Fe3+) was obtained from the empirical formalism based on the primary products and Linear energy transfer (LET) values. The present work aim to determinate the G-value for 192Ir HDR using a new setup elaborated by Radiological Sciences Laboratory group (LCR/UERJ-Rio de Janeiro State University, Rio de janeiro, Brazil). It was performed using a HDR brachytherapy using 192Ir source (GammaMed Plus HDR 232, Varian) at Radiotherapy department of HUCFF - Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, Brazil. The results showed a good statistical response to doses about 22 Gy and dose rates of and the G value calculated was 1.5607·10-6 Plus- Minus Sign·0.0669·10-6 mol.J-1 and type A uncertanty 0.96%.