The appearance of bacterial resistances with all the complications associated to its presence, it constitutes a prob- lem of first line in public health on a global scale. The present study describes in a general form the resistance to antimicrobial in Gram-positive and Gram-negatives microorganisms identified in an IPS of 4 ° level of complexity of Barranquilla during the year 2013; this is why there was checked the information that fulfilled criteria of inclusion of descriptive and retrospective type of the epicentre of microbiology; where there was found 21 % (1.208) cases, predominating over bacilli Gram-negatives and Coccus Gram-positive, presenting more prevalence: Escherichia coli (E. coli) 16.88 %; Klebsiella pneumoniae, (Klebsiella p.) 11.92 %; Pseudomonas aeruginosa (P. aeruginosa) 9.02 %, Staphylococcus Aureus (S. Aureus) 8.70 %, Staphylococcus coagulase-negative (CoNS) 0.41 %. The most frequent infection identified in urine culture with 218 cases, followed by 171 cases in blood culture, 117 cases in soft tissues, finally with 68 cases in respiratory and 2 cases in culture of liquids; being the areas of major infection: Urgencies with 31.44 % (178) cases, followed by 8.65 % (49) cases in hospitalization, 8.48 % (48) cases in coronary ICU, later with 5.87 % (32) cases in pediatric ICU, 4.24 % (26) cases in neurological ICU and 4.4 % (25) cases in the area of 4th floor. The tax of phenotypical profile of resistance found is: In E. coli, they were presented 36.27 % (74) cases of resistance by extended spectrum beta-lactamase (ESBL) and 12.74 % by Carbapenemases (KPC); followed by Klebsiella p, with 36.80 % (53) cases of resistance by ESBL and 26.38 % (38) cases by KPC; S. aureus presented 54.23 % (57) cases of methicillin-resistant Staphylococcus aureus (MRSA) respectively. Being the universe of study all the samples of patients hospitalized due to infectious illnesses; from those antimicrobial used as the prescribed ones, a few of them presented sensibility of 90-100 %, a reason why they could be suggested as an option for treatment of the infections caused by Gram-positives and Gram-negatives agents. It is required to optimize and extend the effectiveness of the antimicrobial available agents and follow the restriction of their uses and the prescription approved by the committee of infections in accordance with the parameters stipulated by the WHO