Community-acquired pneumonia (CAP) is an important cause of morbidity and mortality in adults, with an overall incidence of 1.07 to 1.2 per 100 persons/year, and it especially affects the elderly, with an incidence of 14 per 100 persons/ year in adults ?65 years. CAP has significant long-term effects and that hospitalization for pneumonia is associated with higher long-term mortality. It is worldwide recognized that several risk factors such as underlying medical conditions and a range of lifestyle factors can increase the risk of developing CAP. This review focuses on the main risk factors associated with CAP. Recognizing these risk factors would help us to perform interventions in these specific risk groups with the aim of reducing the rate of CAP.