An epidemic of acute haemorrhagic conjunctivitis affecting persons of all ages and both sexes occurred in Delhi and surrounding areas during the monsoon season of 1994. The symptoms lasted on an average for 4-5 days. In some of the patients corneal involvement was observed. Conjunctival swabs from the affected patients were processed for viral antigen detection, virus isolation and bacterial culture and sensitivity. Viral antigen was detected in 62% (31/50) of the smears tested by indirect immunofluorescence assay. In 22 (44%) of the specimens Coxackie A 24 (Cox A 24) virus antigen and in 9 (18%) of the specimens Entero Virus 70 (EV 70) antigen were detected. In confluent monolayers of Hep 2 cells cytopathic virus was isolated in 10 (30.30%) of the 33 specimens processed. The isolated viruses were identified as either Cox A 24 (7 isolates) or EV 70 (3 isolates) using indirect immunofluorescence assay. Super added bacterial infection was observed in 33% (89/270) of the cases, Staphylococcus albus being the predominant bacteria isolated.