Introduction: The objective of this work is to analyze the bacteriological aspects of surgical site infection at the University Hospital of Marrakech by evaluating the antibiotic resistance profile of the different bacterial strains incriminated over the last three years. It is a descriptive study over a period of 3 years (2018-2020), at the level of the microbiology laboratory of the University Hospital of Marrakech, including all surgical site infections documented over this period in patients operated and hospitalized for at least 72 hours at the level of the different services of the University Hospital of Marrakech and presenting clinically an infection of the surgical site. Results: The prevalence of surgical site infection was 79% out of a total of 332 documented infections. The bacteriological profile was dominated by Gram-negative bacilli with 47.2% of Enterobacteriaceae (n=157) and 15.6% of non-fermentative Gram-negative bacilli (n=50). Escherichia coli dominated this profile with 15.9% (n=53) followed by Klebsiella pneumonia 12.3% (n 41), Pseudomonas aeruginosa 10.8% (n=36). Antibiotic susceptibility analysis identified 25% of multidrug resistant strains. 40% of E.coli strains were resistant to C3G, 60% were resistant to amoxicillin-clavulanic acid, 35% were resistant to gentamycin, 40% were resistant to ciprofloxacin and 55% of strains were resistant to cotrimoxazole. Strains with decreased susceptibility to carbapenems accounted for 10.5% of all enterobacterial isolates. Conclusion: Surgical site infections are common in our setting, represented mainly by gram-negative bacilli, mainly enterobacteria and Pseudomonas aeruginosa. Over the last three years, these hospital germs have increasingly developed a multi-resistance to the antibiotics prescribed in first intention. The implementation of a preventive hospital strategy and the rigorous use of antibiotics are urgent and indispensable.