Carp pox, a putative viral disease exotic to North America, occurred in golden ide 1 yr after the fish were imported into the United States from the Federal Republic of Germany. The raised, white, plaque-like lesions, which occurred on about 5% of the fish, healed spontaneously and caused no mortality. Electron micrographs showed herpesvirus-like particles associated with lesion specimens; however, no infectious viruses were detected in tests with seven warmwater fish cell lines.