The functions of ghrelin, a novel weight-regulatory peptide, have not been intensively investigated in amphibians. The aim of this experiment was to study the effects of exogenous, mammalian ghrelin on the carbohydrate and lipid metabolism of two Palearctic Anurans: the common toad (Bufo bufo) and the common frog (Rana temporaria). Twenty-eight common toads and 20 common frogs were injected daily with purified human Ser3-acylated ghrelin at 10 μg kg–1d–1 or with 0.9 % saline into the dorsal lymph sac for four days. Exogenous ghrelin decreased the plasma total cholesterol (Chol) and LDL-Chol concentrations and increased the HDL-LDL ratios of the common frogs. The liver lipase activities decreased but the fat body lipase activities increased due to the ghrelin treatment. Ghrelin did not influence the measured variables in the common toad. In addition to stimulating growth hormone and prolactin secretion in amphibians, ghrelin also influences their lipid metabolism.