*This article derives as a result of the project "Validation and standardization of quick analytical tests, sensitive and reliable for determining the presence of mercury and methylmercury in shrimp and fish" approved by To develop an analytical methodology for the validation of complete matrix "in-house" for the analysis of Hg in food samples. Materials and methods. The procedure was developed through the digestion with microwaves and the quantification via spectrography of atomic absorption with cold vapor and a system of flow injection (AAS-FIAS). Results. The methodology was optimal for the extraction, for the treatment of samples and the determination. The recoveries were evaluated in enriched samples at two levels (7,0 y 15,00 µg/L Hg) and with two certified reference materials (SRM 2976 y BCR-463) higher than 90% with a relative standard deviation (RSD) lower than 1.5 %. The method showed linearity between 1.00 y 20.00 µg/L, con r 2 > 0,995 and residuals lower than 20%. The limit of detection and quantification was 0.331 y 0.992 µg/L respectively, which are inferior to those reported for the analysis of metals in food. Conclusion. The method is reliable for routine essays and is applicable for the evaluation of the food exposition in accordance with the quality parameters of the Resolution 122 of 2012 from the Ministry of Health and Social Protection of Colombia.