The effect of sweet chestnut (Castanea sativa Mill) flour in stimulating the growth of probiotic bacteria in fermented skim milk produced with different probiotic strains, namely Lactobacillus acidophilus, L. rhamnosus and Bifidobacterium animalis subsp. lactis was evaluated. Microbial counts, pH, total titratable acidity (LA %) and syneresis were measured in fermented skim milk samples. Additionally, the antioxidant capacities of the samples were measured by Trolox equivalent antioxidant capacity (TEAC), free radical scavenging activity (DPPH), and Ferric Reducing-antioxidant Power (FRAP) assays. The viability and growth proportion index (GPI) of L. rhamnosus were significantly higher than those of L. acidophilus and B. lactis in all samples during storage. Results indicated that all probiotic fermented milks enriched with chestnut flour displayed significant probiotic viability (>7 log(10) cfu/g) with high antioxidant capacities. L. acidophilus, L. rhamnosus and B. lactis survived throughout the shelf life of the chestnut-fermented skim milk, and remain at this satisfactory viability level even after 21 days of storage. The antioxidant capacity and phenolic contents were dependent on probiotic strains used.