Lymphocystis disease, affecting snake-skin gouramis (Trichogaster peltoralis) and blue gouramis (T. tricopterus), was diagnosed histologically in 2 shipments of imported tropical fish. Typical virus particles were readily demonstrated by electron microscopy in negatively stained preparations and in sectioned tissues. Attempts at viral isolation in 2 fish cell lines (RTG-2 and FHM) were unsuccessful as were attempts to transmit the infection to pearl gouramis (T. leeri).