PURPOSE: To identify speech-language pathology manifestations presented by children with congenital hypothyroidism, and to investigate the association of such manifestations with the time of diagnosis and beginning of treatment. METHODS: Caregivers of 15 children diagnosed with congenital hypothyroidism who attended the Reference Service on Neonatal Screening of the states of Rondônia and Acre answered a questionnaire in which they should report mainly speech-language pathology complaints. Children's age ranged from 2 to 7 years, 67% of boys and 33% of girls. The average age at the time of diagnosis was 1 month and 3 days, and treatment started, in average, at 1 month and 6 days. The dosage of the drug varied from 5 mg/day to 100 mg/day. RESULTS: The complaints reported were: delay in the onset of oral language, speech alterations, unintelligible speech, agitated and nervous behavior. Some caregivers did not report any complaints. It was found that most subjects had problems with speech (80%), and a few had hearing impairment (7.7%). For those who reported complaints, mean time of diagnosis and beginning of treatment was delayed when compared to those who did not report. CONCLUSION: Speech-language pathology manifestations were reported, especially regarding speech. Moreover, there was association between the presence of complaints and speech disorders with the time of diagnosis and beginning of treatment. It is suggested the inclusion of the speech-language pathologist and audiologist in the team monitoring the development of children with congenital hypothyroidism.