BACKGROUND: Common gastrointestinal disease irritable bowel syndrome (IBS) is marked by symptoms like changed bowel habits, bloating, and stomach ache. A low-FODMAP combined gluten-free diet (LF-GFD) has been suggested as a possible therapy for IBS symptoms management. OBJECTIVE: This study sought to investigate whether a LF-GFD would help patients with IBS. METHODS: Strict inclusion and exclusion criteria from internet databases helped to identify clinical studies evaluating the intervention of LF-GFD in the treatment of IBS patients. Using measurements including the visual analog scale (VAS) for bloating and pain, the IBS symptom severity scale (IBS-SSS), and IBS quality of life (IBS-QoL), the main results evaluated were the efficacy of LF-GFD in reducing IBS symptoms. Furthermore assessed were the psychological impacts of LF-GFD utilizing the self- rating depression scale (SDS) and self- rating anxiety scale (SAS). RESULTS: A total of 437 patients (221 on LF-GFD diet and 216 on GFD) were involved in 4 randomized controlled trials and 4 cohort studies. The combined results indicated that LF-GFD reduced the VAS bloating ratings (RR = - 0.58, 95%CI - 0.92-0.23, P = 0.0010, I2 = 83%) and the VAS pain scores (RR = - 0.42, 95%CI - 0.66-0.19, P = 0.005, I2 = 58%). In addition, LF-GFD indicated a substantial enhancement in IBS-SSS scores (MD = - 1.42, 95%CI - 2.74-0.10, P = 0.03, I2 = 24%) and IBS-QoL ratings (MD = 3.75, 95%CI 0.98-6.53, P = 0.008, I2 = 33%). Moreover, the LF-GFD group showed a substantial drop in SDS (MD = - 2.56, 95%CI - 3.38-1.74, P < 0.00001, I2 = 65%) and SAS (MD = - 4.30, 95%CI - 6.53-2.24, P < 0.0001, I2 = 0%) scores compared to the GFD group. CONCLUSION: LF-GFD therapy significantly enhances clinical symptoms and reduces anxiety and depression in individuals diagnosed with irritable bowel syndrome.