Quality control is a useful tool in the safe diagnosis of trading products. This study aimed to perform physicochemical, microbiological quality control of six probiotic natural flavor yogurt samples. Six samples were used in the study: I1: probiotic Direct Vat Set culture (DVS) Bifidobacterium + traditional milk; I2: DVS culture + delactosed milk; I3: work culture + L. paracasei + traditional milk; I4: work culture + L. paracasei + delactosed milk; I5: commercial yogurt + commercial L. casei + traditional milk; I6: commercial yogurt + commercial L. casei + delactosed milk. Physicochemical analyses were run in the samples: pH, titratable acidity, fat content, Defatted Dry Extract (DDE) and viscosity. Microbiological analyses were also assessed: Determination of Most Probable Number (MPN) of total and thermotolerant coliforms and Enumeration of Yeasts and Molds (EYM) following the methodology recommended by the legislation. The samples were labelled as probiotic with lactic acid bacteria counting between 1.40x108 to 1.00x1010. The physical-chemical analyses did not present statistical differences except for the fat content: the whole sample I1 (3.05%), semi-skimmed I2, I3, I4 and I5 (0.7%-2.95%) and I6 skimmed (0.45%). Acidity levels were in accordance with the legislation from 88 °D 107 °D. The pH was in the specific range of casein coagulation with samples average of 4.6%. All samples presented high dry extract content, above 20.3%, due to the addition of powdered milk, which increases nutritional value, prevents syneresis and improves viscosity. Viscosity values ranged from 2300.0 to 6500.0 cP. MPN of total and thermotolerant coliforms registered, comply with the standards established by the legislation. The presence of filamentous fungi and yeasts was not detected. All the samples were physic-chemically and microbiologically adequate, except I5 and I6, which failed the criterion of percentage fat, differing only 0.1 and 0.8 percentage points, respectively.