Gestational diabetes mellitus (GDM), which accounts for 86% of pregnancy-related hyperglycemia, is a kind of pregnancy-related glucose intolerance that results in hyperglycemia. Compared to prospective mothers who are healthy, pregnant women with GDM are more likely to develop maternal and neonatal issues. There has been a lot of focus on the problems with pregnant women's mental health, especially the high-risk population of GDMs. Studies show that melancholy and anxiety, in addition to physiological factors, are important causes of gestational diabetes. It is important to completely comprehend the degree of gastrointestinal microflora changes that cause GDM and depression as well as their causative relationship with bacterial commensals. Aim of the review is to discuss the association of gut microbiota dysbiosis and the possible mechanistic links between the gut microbiota in women and GDM as well as the association between maternal gut dysbiosis and pregnancy outcome.