Abstract Fusarium oxysporum is the most common and wide spread pathogen of chickpea in 32 different countries including Iran. The purpose of this investigation was to clarify the state of this pathogen on chickpea in Iran with the emphasis on the Khorasan Razavi and Khorasan shemali provinces. In this study sampling was carried out in 52 fields in Khorasan and a total of 70 Fusarium isolates were recorded. Of these, only 16 isolates proved to be F. oxysporum and the rest belonged to other Fusarium species. A pathogenic test was performed on susceptible Jam variety. The host reaction included a wide range of disease symptoms ranging from nonpathogenic to severe pathogenic. Studying the morphological and physiological characteristics of the 16 isolates revealed a diversity among some of these isolates. DNA extractions was carried out on the 12 Khorasan isolates and 13 isolates of Tabriz, Urmia, Ilam, Kerman, Kermanshah and Lorestan. RAPD molecular markers showed a high genetic variation among examined isolates. These markers distingushed pathogenic isolates from nonpathogenic owns. The dendrogram analysis did not show any genetical correlation for regional and climatical factors. Among the primers tested Four bands had high correlation with pathogenicity and presented only in four isolates with high pathogenicity

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