Chinese prescription Kangen-karyu, comprised of six crude drugs, has received much attention due to its numerous biological activities. The present study reports therapeutic evidence for Kangen-karyu from pre-clinical animal experiments related to human diseases. Kangen-karyu showed beneficial effects on type 1 diabetes and related complications through the suppression of protein expression related to advanced glycation endproducts and oxidative stress. Kangen-karyu reduced oxidative stress via the regulation of dyslipidemia, and also exerted a renoprotective effect mainly through its antioxidant properties during the development of diabetic nephropathy in type 2 diabetes. In addition, Kangen-karyu showed neuroprotective effects by attenuating the spatial memory impairment and neuronal death induced by diabetes. Kangen-karyu counteracted oxidative stress and ameliorated tissue damage possibly associated with aging. These findings provide scientific evidence to explain the efficacy of Kangen-karyu based on its underlying therapeutic effects.