Twenty laying hens (Hy Line) kept in individual cages were randomly divided into two groups, B and BG. Both groups were fed a basal diet ad libitum, hens from group BG additionally received 25 g of fresh chopped grass per day in separate feeders. The experiment lasted twelve days, at the end all birds were slaughtered and the content of the caecum was sampled. Total and individual short-chain fatty acid (SCFA) concentrations in caecal contents were measured by high pressure liquid chromatography. The total amount of SCFA in caecal digesta of hens fed diets with added fresh grass was lower by 27% in comparison with group B (P≤0.05), however, the proportions between acetic, propionic and butyric acids were similar in both groups. In both groups the level of acetic acid was highest followed by propionic and butyric acids (P≤0.05).