Introduction: The benefit of adequate starting of empirical antimicrobial therapy over mortality and length of hospital stay in critical care patients with sepsis, bacteremia and nosocomial pneumonia is clear. Nevertheless, such benefit has not been established among non critical hospitalized patients, this benefit is not established. Methods: An observational analytic study was carried in 216 non critical patients who were hospitalized at Hospital Pablo Tobon Uribe between October 2008 and January 2009 because of suspected community and in-hospital acquired infectious diseases, in whom a positive microbiologic culture was obtained and who received empirical antimicrobial therapy, classified as adequate or inadequate based on the sensibility of the isolated bacteria of the sample taken at the time of beginning such therapy. Results: Out of total samples, 139 were classified as adequate therapy and 75 as inadequate. Mortality in the adequate therapy group was 5.7% and in the inadequate group, 2.6% (RR 2.16 CI 95% 0.47-9.9, p value=0.30.), the average of hospital stay lenght from the beginning of the hospitalization was 10 days in the adequate therapy group (IQR 7-18) and 12 days in inadequate therapy (IQR 5-7), p value 0.034. Conclusion: In non critical patients who develop infectious disease of any kind, requiring in-hospital management and in whom antimicrobial empiric therapy is started, early beginning and effective antimicrobial coverage do not offer significant benefits over mortality, although it does have a benefit regarding length of stay.