1. It was found that anserine and carnosine form with o-phthalic aldehyde coloured reaction products of identical molar coefficient of absorption at 640 nm. Hence, a simple and rapid method for spectrophotometric determination of these dipeptides has been worked out. The method was applied to determine the sum of anserine and carnosine in muscles of adult geese, (female). Carnosine was determined with enzymatic method. 2. Ratio between anserine and carnosine concentrations depends on animal age (lower in 1-yr-old geese than in 2- and 3-yr-old ones) and type of muscles (lower in leg muscles compared to breast muscle). 3. Correlation was found between level of carnosine and level of anserine--it depended both on geese and type of muscles.