The link between gut microbiota composition, insulin resistance, and diabetes has been recently proposed. As such, the impact of probiotics on improving glycemic control has been reported recently. Although probiotics have attracted much interest as a complementary approach to improve glucose metabolism, the mechanisms underlying their actions remained to be determined. Hence, here we aim to review the mechanisms by which the probiotics might affect glycemic control. Probiotics improve glycemic control through diminishing fermentation of polysaccharides, suppressing inflammation, act as bile acid de-conjugate hydrolase, increase the bioavailability of Gliclazide drugs and changes in incretin secretion. However, the pathway behind the effect of probiotics on glycemic control is complex with many interplay interactions. The involvement of multiple mechanisms may explain the ambiguities in determining the exact mechanism that is behind this effect. Manuscript profile