BACKGROUND: Chronic wounds are considered a public health problem that may be complicated by bacterial infections, mainly caused by resistant strains. AIM: To study the bacteria prevalence and antimicrobial susceptibility in samples from adult patients with chronic wounds. METHODS: Patients treated at National Institute of Wounds Foundation between May and July 2014, with chronic ulcers in lower extremities with clinical inflammatory signs were recluted. Samples were cultured in aerobic and anaerobic atmosphere and species identification was performed by API (Biomerieux) galleries. The in vitro susceptibility was evaluated according to the Kirby Bauer method. RESULTS: From 73 patients, 46 had infected wounds most of them were venous ulcers (33) with prevalence in polymicrobial infections and 10 with foot-diabetes ulcers with prevalence in monomicrobial infections (p ≤ 0.05). Sixty-eight strains were isolated and Enterobacteriaceae were predominant in monomicrobial infection (p ≤ 0.05) and the other groups were slightly higher in polymicrobial infection. The main species were Staphylococcus aureus (24%) followed by P. aeruginosa (18%). Fifty strains (77%) were resistant or multi-resistance. We emphasize resistance of S. aureus to ciprofloxacin (50%) and cefoxitin (37.5%), thus identifying resistance to methicillin in the community (CA-SAMR), all of which are sensitive to cotrimoxazole. Enterobacteria showed sensitivity to amikacin (95.5%), P. aeruginosa showed resistance to ciprofloxacin (33.3%) with high sensitivity to gentamicin (91.7%) and amikacin (83.3%), while Acinetobacter spp showed resistance to ciprofloxacin and ceftazidime in 60%, with 100% sensitivity to imipenem. 50% Streptococcus ß hemolytic showed resistance to clindamycin and penicillin. CONCLUSION: These data provide epidemiological information on chronic wound infections, representing support for diagnosis, treatment and management of this pathology.