To identify the papillomavirus types associated with condylomata acuminata in children and to evaluate their mode of transmission, we studied 32 children with anogenital warts. External condylomata were found in 12 of their mothers and in 10 of their fathers. Ten mothers, including two without external lesions, had cervical condylomata. Blot hybridization studies disclosed a genital human papillomavirus (HPV) in 14 of 27 children (HPV-6 in 12 and HPV-11 in two) and in 8 of 14 patients (HPV-6 in all). HPV-6 was found in another child by the polymerase chain reaction technique. Infection occurred most likely at birth or from nonsexual contact, but sexual abuse could not be excluded in one 11-year-old girl. Cutaneous HPV-2 was found in seven children and as yet uncharacterized papillomaviruses were found in two children. Three mothers of HPV-2-infected children had common hand warts, and two children had subungual warts. This study shows the frequent nonsexual transmission of genital papillomaviruses in children and the unexpectedly high association of children's condylomata with papillomaviruses responsible for skin warts, possibly transmitted by heteroinoculation or autoinoculation.