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, affiliation 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% confidence 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 Pacific Coast had a higer probability of presenting bilateral clinical manifestations (OR 4,61 95%CI 1,13-18,93). Discussion: Social factors influencing 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 influence the prevalence of oral clefts.