In this study, the content of bioactive compounds (polyphenols and tetraterpenoids), antioxidative activity, and inhibitory activities toward α-amylase, α-glucosidase, cholinesterase of different cultivars of peach kernels were measured. Such results have not been published so far. It has been shown that peach kernels were characterized by a similar profile of bioactive compounds as the peach fruit, however, the content of some of these compounds was completely different. The total content of polyphenols ranged from 12.7 to 3.8 g/100 g dm, the carotenoids contains were from 101.7 to 0.0 mg/100 g dm and the amount of cyanogenic glycoside ranged from 245.7 to 17.4 mg/100 g dm. The peach kernels were also characterized by high antioxidative potential and the ability to inhibit enzymes linked to obesity, type 2 diabetes and Alzheimer's disease. The study showed that the health-promoting properties of peach kernels are stimulated by polymeric procyanidins, hydroxycinnamic acids, carotenoids and cyanogenic glycosides. Generally, it was confirmed that peach kernels could be a valuable source of polyphenols used by the pharmaceutical industry for the production of dietary supplements to support the prevention of chronic non-communicable diseases.