Summary This study compared the impacts of intragastric balloon (IGB) therapy and intensive lifestyle modification therapy on abdominal fat distribution. Sixteen extremely obese Japanese patients were assigned to an intensive lifestyle modification therapy group with educational hospitalisation (8 patients) or an IGB therapy group (8 patients) and were followed up for 6 months. The main outcome measures were the differences at 6 months, relative to the baseline values, in the visceral fat area (VFA), subcutaneous fat area (SFA), and liver volume as measured using computed tomography. At 0 month, the body weights (BWs) were 121.3±19.0kg and 127.1±24.4kg and the VFAs were 299±55cm2 and 257±56cm2 in the intensive lifestyle modification therapy group and the IGB therapy group, respectively. No statistically significant differences in the baseline characteristics were observed between these two groups. At 6 months, no difference in the changes in BW from the baseline value (−11.5 [−16.4, −6.6]kg vs. −11.2 [−18.9, −3.4]kg) was seen between the two groups. However, a statistically significant difference in the change in the VFA (−66 [−87, −44]cm2 vs. −22 [−70, 26]cm2 [P=0.027]) was observed; no significant changes in the SFA or liver volume were seen. In conclusion, IGB therapy was as effective as intensive lifestyle modification therapy for weight reduction but was less effective with respect to the improvement in abdominal visceral fat accumulation and liver steatosis in super-obese Japanese patients.