Carnosine (b-alanyl-L-histidine) is known to be a natural neuropeptide with a variety of protecting properties preventing neuronal cell death under conditions of oxidative stress. Its antioxidant (Severin et al, 1984; Aruoma et al, 1989; Boldyrev et al, 1999), immunomodulating and wound healing (Nagai and Suda, 1989) as well as radioprotective and anti-ischemic (Boldyrev and Severin, 1990; Gallant et al, 2000; Stvolinsky et al, 2002) abilities could be useful tool to prevent accumulation of senescence features (Hipkiss, 1998). We have tested anti-senescence effect of dietary carnosine measuring life-span of two laboratory species, fruit-fly Drosophila melanogaster (D-32 strain) and laboratory mice with accelerated senescence, Senescence Accelerated Mice prone, SAMP. The average life-span of D. melanogaster females and males was 42.4±1.4 and 29.2±1.3 day respectively. When carnosine (0,02-0.2 mg/l) was added to the every-day fruit flies diet the life-span of females was not changed significantly while that of males increased till 36.9±1.2. In both cases partial metabolisation of carnosine was demonstrated followed by subcequent accumulation of histidine. When SAMP were grown on the diet containing carnosine (100 mg/kg body weight) 17-22% increase in average life-span was found with slower accumulation of senile features, better learning ability and normalized activities of brain monoamine oxidase B and superoxide dismutase. The conclusion was made that carnosine possesses pronounced anti-senescence effect in vivo.