An Epstein-Barr virus (EBV) genome-positive epithelial hybrid cell line, NPC-KT, derived from the fusion of primary nasopharyngeal carcinoma cells with a human epithelial cell line of adenoid origin and a subline of EBV genome-positive Ramos cells, Ramos/NPC, converted after infection with NPC-KT EBV have been previously described (Takimoto et al., 1984; Takimoto et al., 1987). The NPC-KT cells produce virus (NPC virus) with both transforming and lytic properties. In this study, NPC-KT and Ramos/NPC cells were examined for the presence of the EBV receptor as measured by the capacity to absorb radio-labelled P3HR-1 and NPC viruses. It was determined that only P3HR-1 virus can attach to NPC-KT cells. Also, the relative concentration of NPC virus receptors on Ramos/NPC cells was found to be significantly reduced when compared to EBV genomenegative Ramos cells, whereas the relative concentration of receptors for P3HR-1 virus was similar to parental Ramos cells. The results suggest that there are differences at least in part of the receptors for P3HR-1 and NPC viruses.