Intra-abdominal infection (IAI) is a frequent complication found in surgical intensive care unit (SICU) and continues to be associated with considerable mortality. Tigecycline, the first-in-class glycylcycline has demonstrated a broad spectrum of activity against a wide range of bacteria commonly found in IAI. This observational retrospective study aimed to describe the experience with tigecycline for serious nosocomial IAI in the SICU. Data were collected from 23 consecutive patients admitted to SICU with serious nococomial IAI who had received empirical treatment with tigecycline. In all cases, IAI was diagnosed via emergency surgery. Severe sepsis was found in 56.5% and 43.5% developed septic shock. Oncological disease was the most common comorbidity (60%). The mean Simplified Acute Physiology Score (SAPS) III within 24 hours from IAI diagnosis was 57.5±14.7, and 87% showed a McCabe score >1 (2 or 3). Escherichia coli was the most common pathogen (43.5%), followed by Bacteroides spp. and Streptococcus spp. (30.4%, respectively). All but one patient received tigecycline in combination (95.7%), particularly with fluconazole (52.2%), followed by piperacillin-tazobactam (43.5%). Empirical antibiotic therapy was considered adequate in 95%. The mean duration of treatment was 8.5±4.5 days. A favorable response was achieved in 78%. Failure of the antibiotic therapy was not observed in any patient. None of the patients discontinued tigecycline due to adverse reactions. SICU mortality was 13%, with no deaths attributable to tigecycline. These findings suggest that tigecycline combination therapy is an effective and well tolerated empirical treatment of serious nosocomial IAI in the SICU.