The morbidity of leptospirosis among children from Ciego de Avila Province was investigated from 1982 to 1995, and 253 cases were diagnosed. Isolated cases prevailed over those occurring in outbreaks. The 10-14 age group was predominant, followed by the 5-9 age group. According to sex, it was more frequently found in males than in females. One death occurred during this period. There was an increase of cases from July to August and October, and November showed a higher incidence of cases. Fever, headache and myalgia were the symptoms and signs more frequently reported, and 92% of cases showed no icterus. Acute fever, leptospirosis and viral meningoencephalitis were the presumptive diagnoses most frequently made. Possible sources of infection involving a larger number of cases were contact with low terrains and bathing in rivers, ponds and lakes. Regarding diagnosis, 162 cases were diagnosed by the microagglutination test and 91 by the hemolytic test. Canicola, australis and pomona were the serogroups more frequently detected by the microagglutination test.