A quantitative inheritence study of leaf form in the garden pea, Pisum sativum L., was carried out using an eight parent F¹ half diallel cross. The inheritance of yield and its components were also studied. The parental lines used for the diallel contained combinations of the following genes which act in the homozygous recessive condition = af. converts normal pea leaflets to tendrils, tl converts normal pea tendrils to leaflets and st reduces the size of the stipule. A combination of af. and tl together results in a mass of small leaflets. The characters measured included length, width, areas and weights of leaflets, stipules and tendrils and the components of yield. The data from the twenty-eight F¹ crosses and their eight parents were analysed with Hayman-Jinks diallel method. The adequacy of the additive-dominance model was determined by the relationships of Wr and Vr: the analysis of variance of (Wr - Vr), the Wr on Vr regression analysis and the WrVr graphical analysis. The results indicated the predominance of additive genetic variance for the vegetative characters although dominance variance and non-allelic interactions were important. The inheritance of yield and its components were mainly attributable to additive genetic variance while the type of dominance varied from partial to complete for both types of characters. Heritabiity was high for the vegetative characters and medium to low for the components of yield.