An epidemic of acute conjunctivitis occurred in Delhi during July-September 1986. The clinical presentation in total of 350 patients were characteristic of acute haemorrhagic conjunctivitis (AHC). Bacterial cultures from conjunctival swabs were sterile in 85 out of 105 (80%) patients, virus cultures in Vero and HeLa cells were negative in 30 patients. However, conjunctival scrapes from 20/30 (66.7%) patients showed specific cytoplasmic fluorescence with enterovirus 70 (EV 70) antiserum, suggesting EV 70 to be the etiologic agent of the epidemic.