Objetivo: caracterizar la mortalidad de la poblacion adulta de 20 a 64 anos residente en la ciudad de Medellin, entre los anos 1994 a 2003, segun causa de muerte y sexo. Materiales y metodos: estudio descriptivo longitudinal retrospectivo de las principales causas de muerte de los adultos de Medellin; con fuente de informacion secundaria de los certificados de defuncion registrados por el Departamento Administrativo Nacional de Estadisticas DANE en la decada 1994-2003. Resultados: durante los diez anos de estudio, entre las primeras causas de muerte se evidencio que las agresiones cobraron el mayor numero de victimas, especialmente los causados por ataques con armas de fuego y explosivos y con instrumentos cortantes y punzantes, en los hombres y mujeres entre 20 y 44 anos. El infarto agudo del miocardio para los hombres y mujeres entre los 45 y 64 anos de edad ocasiono un gran numero de muertes en este grupo poblacional. A pesar de no presentarse el Sindrome de Inmunodeficiencia Adquirida entre las primeras causas se muerte, si se manifesto durante los ultimos anos de estudio en hombres y mujeres con edades de 20 a 44 anos; para las mujeres ocupo la quinta causa durante 1998 y 1999 y para los hombres la tercera causa durante los ultimos tres anos 1997, 1998 y 1999. Conclusiones: las causas de fallecimiento de los hombres adultos de 20 a 64 anos residentes en Medellin, ocurridas en la decada 1994-2003, estuvieron origen en una causa externa y en enfermedades del sistema circulatorio; las defunciones de las mujeres en este mismo rango de edad fueron originadas por tumores o neoplasias y en enfermedades del sistema circulatorio, mostrando el mayor riesgo al que estan expuestos los hombres de morir por causa violenta inflingida o autoinflingida que las mujeres (OR=7,73) y las mujeres presentan un riesgo mayor que los hombres de morir a causa de tumor o neoplasia (OR=4,66). Abstract Target: to characterize the mortality of the adult population from 20 to 64 years old, resident in the city of Medellin, between the year 1994 to 2003, according to the cause of death and sex, Materials and methods; descriptive longitudinal retrospective study of the main causes of death of the adults of Medellin; with source of secondary information from the certificates of death registered by the Administrative National Department of Statistics in the decade 1994-2003. Results: During ten years of study, among the first causes of death it was shown that the aggressions resulted in the biggest number of victims, especially the ones caused by attacks with firearms and explosives and with cutting and pointed instruments, in men and women between 20 and 44 years. The acute infarct of the myocardium for men and women between 45 and 64 years of age caused a large number of deaths in this opulation group. In spite of the fact that deaths resulting from the Acquired Immunodeficiency Syndrome was not among the first causes of death, the Syndrome appeared during the last years of study in men and women with ages from 20 to 44 years. For the women it occupied the fifth cause during 1998 and 1999 and for the men the third cause during the last three years 1997, 1998 and 1999. Conclusions: The causes of death of adult men from 20 to 64 years old, resident ofMedellin, that took place in the decade 1994-2003, were the result of an external cause and of illnesses of the circulatory system. The deaths of women in the same group of age were caused by tumors or neoplasias and by illnesses of the circulatory system. This shows the biggest risk to which the men are exposed of dying as result of violent cause, both received o self-inflicted in comparison with women (OR=7,73), and women have a higher risk than men of dying from tumor or neoplasia (OR=4,66). Key words: Mortality, cause of death, Medellin.