We conducted a randomized controlled trial to investigate the efficacy and safety of a system for online glucose monitoring of type 2 diabetes patients. The software automatically filtered the self-monitored blood glucose data to reduce physicians' time. In the control group, the physicians had to contact the patients manually. We measured the time spent by physicians for online management in a 24-week study. Seventy-nine patients were recruited. The frequency of physicians' online monitoring of the patients was decreased by 55% in patients with HbA(1c) ≤ 6.5% and by 29% when HbA(1c) > 6.5% (P < 0.01). Physicians' log-in time was reduced by 67% and 55% in patients with HbA(1c) ≤6.5% and >6.5%, respectively (P <0.05). HbA(1c) levels were maintained at <6.5% during the study period in both groups. The study showed the efficacy and safety of the software for online communication in diabetes management. The results suggest that it could improve the cost-effectiveness of online communication systems and form the basis of future clinical applications.