BACKGROUND Campylobacter jejuni and Campylobacter coli represent one of the main causes of bacterial diarrhoea in humans. Although the disease is usually mild and self-limiting, severe chronic sequelae may occur, such as reactive arthritis, Guillain-Barré and Miller Fisher syndromes. Serotyping is used as an epidemiological marker, while post-infective polyneuropathies are associated with several O serotypes. OBJECTIVE Strains of C. jejuni and C. coli were serotyped based on heat stable (HS) and heat labile (HL) antigens, as well as biotypes to determine strain diversity. METHODS Campylobacter spp. was isolated using selective blood media with antibiotics. Differentiation to the species level was done by a combination of biotyping tests and by a PCR-based RFLP test. The isolates were characterised by Penner and Lior serotyping methods. RESULTS The serotypes showed diversity without predominant serotypes. 24 HS serotypes were detected among 29 C. jejuni strains, and seven serotypes among nine C. coli strains. HL serotyping method successfully typed 62.5% of strains. Among 16 C.jejuni strains 14 serotypes were detected, and three among four C. coli strains. A C.jejuni strain associated with a patient with Guillain-Barré syndrome was typed as biotype II, O:19. CONCLUSIONS The biotyping and serotyping results have indicated that C. jejuni and C. coli strains in the region of Nis, Serbia are diverse and could be probably of unrelated sources of origin or reservoirs. The strain associated with the Guillain-Barré syndrome patient was serotype O:19, one of the most common in this post-infective complication.