Individuals infected by the human immuno deficiency are more prone to suffering certain bacterial infections in the course of their clinical evolution. The agents involved in these infections are: Streptococcus pneumoniae, Haemophilus influenzae, Pseudomonas aeruginosa, Salmonella spp and Campylobacter spp, which occasion an increase in morbidity and mortality. With a lower frequency, but with an equal morbidity and mortality, infections have been found caused by Rhodococcus equi, Nocardia spp and Bartonella spp. Even though all of them account for a selective impairment of immunodeficiency in one way or another, their incidence varies. Other factors such as degree of immuno suppression, habits, social and geographic living environment could be important. In general, there is a lack of chemoprophylactic strategies for their prevention. Early diagnosis and correct treatment could have important advantages for the quality of life and survival of these patients