OBJECTIVE: To describe and to compare the incidence of tuberculosis in childhood and adolescence in the Paraíba Valley (State of São Paulo, Brazil) in 1993 and 1997. METHOD: Descriptive study with secondary records obtained from the Tuberculosis Division of the Health Department of the State of São Paulo (Divisão de Tuberculose da Secretaria de Saúde de São Paulo). The variables were the type of case, age, form of detection, diagnosis confirmation, clinical presentation, X-ray results, and anti-HIV test results. RESULTS: The global incidence of tuberculosis in all age ranges was of 97.3 cases/100,000 inhabitants in 1993, and 127.6 cases/100,000 inhabitants in 1997. In the age group up to 15 years old, there were 93 new cases in 1993, and 68 new cases in 1997, representing an incidence of 11.7 cases/100,000 inhabitants in 1993 and 7.9 cases/100,000 inhabitants in 1997. The most common clinical presentation was the pulmonary form; the most important form of detection was by searching communicants; the most frequent diagnosis confirmation was by X-ray, and there was an increasing number of anti-HIV tests between 1993 and 1997. The distribution by age range was similar to the literature data in both years analyzed. CONCLUSION: The values of tuberculosis incidence in childhood and adolescence found in this study are higher than those existing in developed countries.