Background: Powdered infant formulas (PIF) play role in infant nutrition when breastfeeding is not available. However, both dairy companies and consumers encounter challenges related to PIF physicochemical stability, microbiological quality throughout storage. Methods: Study aimed to evaluate physicochemical stability and microbiological quality of eleven PIF samples, collected in Algiers city, Algeria, during spring season (February- April) of 2023. Results: Chemical tests showed stable samples, with following values: Density (1.024±0.005), pH (6.655±0.176), Acidity (17.628±0.3514), Viscosity (2.574±0.2577), Conductivity (1805.72±68.397μS/cm), Total Dissolved Solids (85±8.9493 mg/L), FAT (3.96±0.4664g/100ml), Protein (1.66±0.2865g/100ml), Lactose (1.5509±0.10446 g/100ml). Microbiological analysis revealed following flora: yeasts and molds present in 36.36%, total bacterial count 27.27%, total coliforms 9.09%, total fecal coliforms 9.09%, Escherichia coli 9.09% and D-Streptococcus 18.18%. Conclusion: Samples seem chemically stable throughout storage, with no flaws in labeling or packing. Consequently, in line with Algerian standards. These samples, however, are not up to Algerian microbiological standards. In perspectives, It is preferable to conduct thorough studies using larger sample sizes in order to understand the sources of contamination.