Introduccion y Objetivo : Determinar la prevalencia de labio y paladar hendido (LPH) en pacientes atendidos en el Hospital Infantil Los Angeles de la Ciudad de Pasto (Colombia) y sus factores relacionados. Material y Metodos: Estudio transversal con la informacion de 223 historias clinicas de pacientes con LPH durante el periodo 2003- 2008. Como variables se tuvieron en cuenta: Sexo, estructuras comprometidas, edad al inicio de tratamiento, estrato socioeconomico, afi liacion al Sistema de Seguridad Social en Salud -SGSS-, capacidad de pago. Analisis univariado y bivariado y se estimo la probabilidad de mayor afectacion de 2 estructuras (labio y paladar) y de manifestacion clinica bilateral, por medio de Odds Ratio (OR) con sus intervalos de confi anza al 95% (IC95%). Resultados: El 66,4% de la poblacion infantil analizada iniciaron su tratamiento despues de haber cumplido su primer ano de edad. El 95,1% de los casos pertenecen a los estratos 1 y 2 y el 69,5%% no tienen capacidad de pago. Los hombres afi liados al regimen subsidiado presentaron mayor probabilidad de manifestaciones clinicas bilaterales (OR 3,41 IC95% 1,13- 10,30) y las mujeres sin afi liacion tuvieron mayor probabilidad de presentar dos estructuras comprometidas (OR 3,09 IC95% 1,09- 8,79). Los hombres que procedieron de la costa pacifi ca tuvieron mayor probabilidad de manifestaciones clinicas bilaterales (OR 4,61 IC95% 1,13-18,93). Discusion : Se encontraron algunos factores sociales que infl uyeron en la prevalencia de LPH; con mayor probabilidad de afectacion en determinados grupos. Se requiere profundizar en la historia familiar y otros factoresque infl uyen en la epidemiologia del LPH. Abstract: Introduction and Objetive: To determine the prevalence of oral clefts (lips and palatal) in patients attended in the ;Los Angeles; Children's Hospital in the city of Pasto (Colombia) and its related factors. Material and Methods: Cross sectional study with the information of 223 clinical charts of patients with oral clefts during the period between 2003-2008. Variables included: Sex, affected structures, age at the beginning of the treatment, socio-economical position, affi liation to the Social Security System, payment capacity. Univariate and bivariate analyses were conducted. An association between the higher probability of 2 affected structures and bilateral clinical manifestation according to different variables was estimated by means of Odds Ratio (OR) and the 95% confi dence interval (94%CI). Results: 66,4% of analyzed children began the treatment before one year of age. 95,1% of cases were patients in the two lowest socioeconomic levels and 69,5% of families did not have payment capacity. Males with subsidized social security were more likely to present bilateral clinical manifestations (OR 3,41 95%CI 1,13- 10,30), while females with no social security were more likely to present two affected structures (OR 3,09 95%CI 1,09- 8,79). Males from the Pacifi c Coast had a higer probability of presenting bilateral clinical manifestations (OR 4,61 95%CI 1,13-18,93). Discussion: Social factors infl uencing the prevalence of oral clefts were observed with a higher probability in certain groups. It is necessary to analyze factors such as the family background and other related factors that infl uence the prevalence of oral clefts.