OBJECTIVES: Streptococcus pneumoniae is one of the most important etiologic agents of both, respiratory infections and systemic invasive diseases, with significative rates of morbidity and mortality in the elderly, which represents an economic burden. There are few published studies describing the cost of care for elderly patients with pneumococcal disease in Latin America. The goal of this study is to estimate the direct medical costs of the acute phase of pneumococcal diseases, it´s complications and sequelae in elderly patients in Mexico, regarding the perspective of the Social Security Mexican Institute (IMSS). METHODS: Resource use in the treatment of pneumonia, bacteremia, meningitis and acute otitis media (AOM) was extracted from 112 clinic files of patients ≥50 years with confirmed diagnosis of pneumococcal disease, treated at Guadalajara, Monterrey and Mexico City hospitals, using a micro-costing approach (bottom-up strategy). Items included in the analysis were: drugs, laboratory tests, outpatient and inpatient care, rehabilitation, procedures and surgical interventions. Resource use for the treatment of complications and sequelae were derived trough a Delphi panel (n=13, infectologists, pediatricians and internist physicians, IMSS). Concordance index for the Delphi panel results was estimated.  The unit cost of medical resources was extracted from institutional source. RESULTS: : The estimated direct cost (2011 US) associated to acute phase of pneumococcal diseases were: AOM $323, outpatient pneumonia $172, inpatient pneumonia $4,718, bacteremia $7,698, meningitis $10,687. Cost of complications (such as systemic, respiratory, cardiac, etc.) was: AOM US$671, outpatient pneumonia US$1,502, inpatient pneumonia US$5,157, bacteremia US$11,267, meningitis US$8,060. The costs of sequelae (such as cardiac, neurologic, auditive, etc.)  were:  AOM US$593, outpatient pneumonia US$18, inpatient pneumonia US$1,560, bacteremia US$ 1,573, meningitis US$13,297. CONCLUSIONS: The high institutional costs associated with pneumococcal disease, as well as its complications and sequelae, merit that decision makers maintain and promote prevention policies for this disease in the elderly.