The evaluation of the potentiality for Lactobacillus acidophilus and/or Lactobacillus rhamnosus bacteriocins with 3% inulin to inhibit Aspergillus niger and Saccharomyces cerevisiae growth in skim milk yoghurt was planned in this study. The manufactured yoghurt samples were examined for the starter cultures count, Aspergillus niger and Saccharomyces cerevisiae counts every 3 days till the appearance of the fungal spoilage. Results demonstrated that Aspergillus niger was not detected in (L. acidophilus bacteriocin and 3% inulin + A. niger 4 log 10 cfu/g) and (L. rhamnosus bacteriocin and 3% inulin + A. niger 4 log 10 cfu/g) yoghurt sample all over the storage period. Saccharomyces cerevisiae counts were decreased by the effect of both bacteriocins; Moreover, L. acidophilus bacteriocin showed higher antifungal activity than L. rhamnosus bacteriocin with 3% inulin. The current study proved that Lactobacillus acidophilus bacteriocin could be used as a natural antifungal agent in yoghurt