At present, majority of legume crops in Ethiopia are grown in the highlands as cool season crops and there production is very poor. On the other hand, we have vast areas of land under arid and semi arid conditions and if we could find a legume suitable to these conditions, we may be able to reduce the gap between the demand and supply for protein in the diet. Therefore; pigeon pea a tropical legume is the one which holds such a promise. Therefore; by considering the importance of pigeon pea in the world economy and its potential for future Ethiopian economy, it is very imperative to increase its productivity and other important traits through genetic manipulation. For genetic improvement of any crop plants, it is prerequisite to know the nature and magnitude of variability present in the available germplasm of the crop.