Study was inspired by the suggestion that interleukin 1-beta (IL-1 beta), one of the major inflammatory mediators, is directly responsible for anaemia of chronic inflammatory conditions. Effect of IL-beta was studied in vitro on methyl cellulose cultures of normal human bone marrow cells, the inoculate having been previously highly enriched in progenitor and stem cells. Our data did not support results reported by others that IL-1 beta is a strong inhibitor of early stages of erythropoiesis in vitro measured by early and late BFU-E formation. About 30% statistically not significant CFU-E inhibition was observed. Above studies show that IL-1 beta role in the development of anaemia associated with chronic inflammatory diseases requires further studies.