In the present study, phenotypical and serological properties of 19Yersinia ruckeri isolates that were isolated from different fish cultivating plants located at different geographical area of Turkey as well as two references seroptypes (serotype 1 and serotype 2) have been compared. Basic microbiological techniques and API 20 E tests that have been employed for phenotypical caracterization provided evidence that isolates have relatively similar structure (although gelatine hydrolysis. Voges-Proscauer and citrate utilisation tests as performed by API 20 E exhibited some differences). Specific colonies of Y. ruckeri were observed on the plates of Shotts-Waltman medium (SWM) and Ribose Ornithine Deoxycholate (ROD) medium. Microagglutination tests that were performed by using Serotype 1 and Serotype 2 revealed that 18 out of 19 isolates were grouped as Serotype 1 while only one isolate was serotype 2. Results of the present study have shown that Yersinia ruckeri Serotype 1 are the most commonly found serotype in our country.