A large outbreak of epidemic keratoconjunctivitis occurred in Alice Springs, Australia, between July and September 1989. Initially, there was a large outbreak within two child care centers, followed by a more prolonged outbreak within the community. A simultaneous outbreak occurred among staff at the local hospital. Infected children developed mild conjunctivitis, whereas adults developed typical keratoconjunctivitis. Conjunctival swabs from 30 cases were cultured and adenovirus was recovered from 18, all of which were typed by neutralization assay as adenovirus type 8. DNA restriction fragment analysis of the genomes of 5 isolates revealed they were identical, distinct from prototype adenovirus type 8, and nearly identical to adenovirus genome type 8C (Ad-8C), which was previously reported in the southern United States in the early 1970s. Ad-8C was present in another region of Australia greater than or equal to 1 year before the epidemic.