Fonio is a traditional cereal that has long been marginalized in Guinean agriculture but is now attracting growing interest from various stakeholders. Therefore, the present study aims to evaluate the effect of fonio processing techniques on its biochemical, microbiological, and sensory qualities. The Association of Official Analytical Chemists (AOAC) method was used to determine the levels of the various parameters. A 44-person tasting panel was organized to assess taste, color, and odor. The results show that the applied processing methods (precooked, parboiled, and roasted) had a significant impact on the biochemical characteristics of fonio, including protein, ash, lipid, and carbohydrates contents. From a microbiological perspective, roasted fonio was the least contaminated by the analyzed microorganisms. However, it is important to note that all three processing techniques produced fonio with generally satisfactory hygienic quality. In terms of sensory attributes, parboiled fonio was the most appreciated for its taste, while precooked fonio received the highest scores for color and aroma. In conclusion, this study highlights the potential for fonio valorization through appropriate processing methods that could enhance its competitiveness and market appeal on local markets in Guinea.