The authors first report in China the detection of HSV-1 antigen in 36 human corneas with recurrent HSK, using the horse radish peroxidase staining technique. The results were that in 16 eyes of quiescent HSK, the HSV antigen was negative, and in 11 of 20 corneas with active HSK, the HSV antigen was positive. When 5 corneas with quiescent HSK were cultured in vitro, 3 again became HSV antigen positive. The findings may be useful in the treatment of HSK.