Type 2 diabetes mellitus (T2DM) is one of the common metabolic diseases worldwide, and studies have found significant differences in the composition and ratio of intestinal flora between patients with T2DM and normal glucose tolerance, and fecal microbiota transplantation (FMT) may modulate the composition of the intestinal microbiota thereby alleviating the hyperglycemic state. We conducted a meta-analysis and systematic review of existing randomized controlled trials (RCTs) to assess the efficacy of FMT in T2DM.We conducted a computer search of PubMed, Embase, The Cochrane Library, and Web of Science to screen randomized controlled trials studies on FMT treatment for T2DM and extracted data from studies that met inclusion criteria. RevMan 5.4 software and Stata 11 software was used for meta-analysis. The indexes of Hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), postprandial blood glucose (PBG), homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides (TG), cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), body mass index (BMI), Aspartate Aminotransferase (AST), Alanine Transaminase (ALT), Systolic blood pressure (SBP) and Diastolic blood pressure (DBP) were mainly evaluated after FMT treatment of T2DM patients, and the changes of intestinal flora were evaluated.Four RCTs met the inclusion criteria and were included in the meta-analysis. Results of the meta-analysis showed that compared with the non-FMT group, FMT combined treatment could significantly reduce the PBG level in patients with type 2 diabetes (MD = -0.51, 95% CI: -1.42-0.40, P = 0.27). Compared with single FMT treatment, FMT combined treatment could reduce TG levels in patients with type 2 diabetes (MD = -0.60, 95% CI: -1.12~-0.07, P = 0.03). The levels of TG (MD = -0.26, 95% CI: -0.51~-0.02, P = 0.03), HOMA-IR (MD = -2.73, 95% CI: -4.71~0.75, P = 0.007) and HDL (MD = -0.06,95% CI: -0.10~-0.02, P = 0.003) were significantly decreased after treatment in the single FMT group. The level of TC (MD = -0.65, 95% CI: -1.00~-0.31, P = 0.0002) was significantly decreased after FMT combined treatment. Compared with before treatment, ALT (MD = -2.52, 95% CI: -3.86~-1.17, P = 0.0002) and DBP (MD = -2, 95% CI: -3.32~0.68, P = 0.003) levels decreased after treatment in the single FMT group and the FMT combined group. FPG (MD = -0.94, 95% CI: -1.86~-0.02, P = 0.04), TG (MD = -0.73, 95% CI: -1.42~-0.04, P = 0.04) and TC (MD = -0.94, 95% CI: -1.45~-0.43, P = 0.0003) were significantly decreased after combined drug and diet therapy. Secondly, FMT can promote the colonization and growth of donor-related flora in patients with type 2 diabetes.In patients with type 2 diabetes mellitus, FMT treatment can reduce the levels of PBG, TG, HOMA-IR, TC, ALT, and DBP, especially in the combined treatment regimen. In addition, FMT can reshape the intestinal flora and establish the balance of dominant flora.© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.