It has been well known that insomnia and sleep deprivation can lead to many metabolic diseases such as type 2 diabete mellitus (T2DM). Chinese medicine (CM) has been used to improve insomnia and showed many good therapeutic effects. Some Coptidis Rhizoma-contained traditional formulae have been found to exert obvious effects on insomnia, such as Jiaotai Pill (???), Huanglian Ejiao Decoction (?????), Huanglian Wendan Decoction (?????), Niuhuang Qingxin Pill (?????), and Zhusha Anshen Pill (????). Coptidis Rhizoma, a traditional herbal medicine which can purge Xin (Heart) fire, is the most important component of these formulas. Studies have found that these formulae could improve T2DM symptoms. We hypothesized that treating insomnia theoretically may help to prevent diabetes and organized many experimental studies in this review and concluded that Coptidis Rhizoma-contained traditional formulae for insomnia might be a potential to prevent diabetes.