La anemia constituye un problema importante de la salud publica que afecta tanto a ninos como adultos. Existen multiples causas que pueden desarrollarla, por lo que su estudio constituye una tarea ardua y a veces de dificil diagnostico. El presente trabajo se enfoca en conocer las causas mas frecuentes de anemia en la poblacion adulta riojana (18–80 anos) que acude a la interconsulta hematologica ambulatoria, en un servicio hematologico privado. A traves de la revision de historias clinicas (362), del periodo de Julio del 2008 a Julio del 2011, se establecio que la prevalecia de anemia fue mayor en mujeres (69%) que en hombres (19%). Los resultados obtenidos sugieren que la anemia de la enfermedad cronica y la deficiencia de hierro son las causas mas comunes y frecuentes en la poblacion adulta. Estadisticamente se establecio una significancia clinica, p-valor 0.001 (a= 0.05), entre las enfermedades subyacentes de un paciente y la edad del mismo, como factores que contribuyen al desarrollo de un sindrome anemico. Most common causes of anemia in an adult population City of La Rioja. Abstract Anaemia is a major problem of public health that affects both children and adults. There are many causes that can develop, so their study is an arduous and sometimes difficult to diagnose. This paper focuses on knowing the most common causes of anemia in adults Rioja (18-80 years) who comes to the outpatient hematology interconsultation in private hematology service. Through medical record review (362), the period of July 2008 to July 2011, it was established that the prevalence of anemia was higher in women (69%) than men (19%). The results suggest that anemia of chronic disease and iron deficiency are the most common and frequent in the adult population. Statistically established clinical significance, p-value 0.001 (a = 0.05), between a patient's underlying disease and age of the same, as factors contributing to the development of an anemic syndrome. Key words: Anemia; Adult; Causes; Multifactoriedad