Objective: To discuss the safety issues of moxibustion therapy in view of moxibustion materials. Methods: The analyses and assessment were performed based on the survey carried out on the use of moxa, modem and ancient records, modern studies, and clinical applications. Results:Moxa has been used as both a medicine and a food for a long history in China. Regarding moxibustion specifically, moxa has been proven to be the optimum choice for moxibustion therapy,through practices and experiments by doctors from different generations. No records have shown any side- or adverse-effects of moxa applied in moxibustion therapy. Conclusion: Moxa has been used in multiple ways for several thousands of years by Chinese people. As the main material for moxibustion therapy, its safety has been proven by documents and clinical practices.