Background: Asthma remains a serious public health problem. Over the last 20 years, three relevant studies on the prevalence of asthma was published in Colombia. In 1992, the point prevalence and cumulative prevalence of asthma in Cartagena (Colombia) were 8.8% and 12%, respectively. Objective: The objective of this study was to estimate the prevalence of childhood asthma in Cartagena in order to contribute to national epidemiological estimates of this disease. Methods: A cross-sectional study in the city of Cartagena. 571 patients have been included, aged 1 to 22 years, of public and private schools through a cluster sampling in two stages. Data collection was carried out during the year 2012. Results: The point prevalence and cumulative prevalence of childhood asthma in Cartagena (Colombia) were 8.7% and 16.1%, respectively. The prevalence of rhinitis and atopic dermatitis were 36.7% and 27.6%, respectively. Conclusions: The prevalence of asthma, allergic rhinitis and atopic dermatitis increases in Cartagena. This upward trend is similar to that found in studies of the International Study of Asthma and Allergy in Children Initiative (ISAAC) in Latin America, which was one of the regions in the world where there was increased prevalence of the three diseases.