Genetic distance among canola cultivars was estimated through multivariate analysis. Thirty cultivars from various sources were analyzed and clustered based upon five morphological characteristics and yield components-crown diameter, number of branches plant(-1), number of pods plant(-1), number of seeds pod(-1) and yield plant(-1) -and placed in three distinct clusters. Two cultivars from each cluster were selected as parents and 15 partial-diallel inter- and intra-cluster crosses were made between the six selected parents and evaluated at two locations in Michigan in 1990/1991. The association between genetic distance and mid-parent heterosis was investigated. The correlation between genetic distance and heterosis was positive and highly significant for seed yield, number of pods plant(-1), and number of seeds pod(-1). Clustering, based on yield and yield-component traits, demonstrated that inter-cluster heterosis was greater than intra-cluster heterosis in the majority of cases.