The aim of this study was to investigate the presence of Herpes simplex virus type 1, in the specimens from patients clinically prediagnosed as herpetic keratitis or keratoconjunctivitis, by virus isolation and direct immunoperoxidase methods. The samples obtained from a total of 33 patients included ulcerated corneal epithelium scrapings and, swabs from ulcer, corneal epithelium, and lower conjunctivas. For virus isolation, both scraping and swab samples for each patient, were inoculated into monolayered Vero cell lines which have previously cultivated on 24-well plates, and examined for the presence of cytopathic effects typical for HSV-1. At the end of 5-days incubation period, the culture media were discarded, the cells were fixed and stained with peroxidase labeled specific HSV-1 antibodies (direct immunoperoxidase--DIP--method). Simultaneously, the smears were prepared from the samples which were sufficient in amount, and stained with DIP method. As a result, cytopathic effects on cell cultures were observed in 4 (12.1%) of the samples, of which 2 were also positive with DIP method. Following DIP staining of smears prepared from 15 samples, HSV-1 antigen positivity was detected in only 1 of the samples. This sample was negative in cell culture. In contrast, one of the 2 cell culture positive samples yielded negative result in smear examination, while the other could not be examined since the sample was not enough. In conclusion, HSV-1 has been shown as the etiologic agent in 3 (9.1%) of our patients clinically prediagnosed as herpetic keratitis or keratoconjunctivitis, and lesion scrapings were determined as the most appropriate samples for virus isolation.