Implantation of a foreign material into human tissue leads to inflammatory and repair reactions, that involve releasing pro-inflammatory mediators such as TNF-Alpha, IL-6 and IL-1Beta. Investigations on cytokine production by cells cultured in contact with new biomaterials can be useful to identify materials better suited for prosthesis and bone implants. The aim of our study was biocompatibility of nitrided surface layers produced under glow discharge conditions on titanium alloy in comparison to titanium alloy in terms of activation of cytokine production and release from human fibroblasts and osteoblasts, i.e. cells responsible for proper biomaterial integration with tissues surrounding the implant. Cells were cultured on disc-shaped specimens prepared from titanium alloy and with surface layer TiN+Ti2N+AlphaTi(N) type for 24 and 48 hours and cytokine contents in culture medium were measured using enzyme linked immunoassay (ELISA) systems. TNF-Alpha induction was not observed in either 24- or 48-h cultures exposed to both types of samples. IL-1Beta was found only after 48h cultivation. Titanium alloy induced higher amounts of IL-1Beta than the nitrided surface layer. IL-6 production was high already after 24h cultivation regardless of the type of titanium sample and increased after 48h. In summary, it was shown that these biomaterials did not activate the typical pro-inflammatory mediator. However, both types of materials activated production of IL-1Beta and IL-6, i.e. cytokines, which despite their pro-inflammatory action, can also play a positive role in bone remodeling. It should be stressed that the biocompatibility of biomaterials is dependent on the balance between a variety of cytokines inducing biological mechanisms connected with bone integration of prosthesis and implants. Our preliminary study shows that IL-6 and IL-1Beta could play an important role in these processes.