An unknown virus which causes mosaic disease on endive (Cichorium endivia L.) was identified as Turnip Mosaic Virus (TuMV) in New Jersey, U.S.A. Collected data about the endive mosaic agent include host range, physical properties, serological and electron microscopical characteristics. All the data confirmed that endive mosaic agent was TuMV, a member of potyvirus group which is mechanically and aphid transmissible. Cryptogram : R/1 : 3.5/5 : E/E : S/C, Ve/Ap. In addition to Cruciferae species this virus is also infectious for some tobacco species and cultivars like Nicotiana glutinosa, N. hybrid, N. tabacum varieties Samsun type and Samsun NN. TuMV causes systemic symptoms on N. glutinosa and N. hybrid and local symptoms on N. tabacum such as spots and oak leaf pattern. It means that TuMV may be considered as another disease agent on tobacco in some parts of the world.