Segregating allozyme and DNA polymorphisms were used to construct a preliminary linkage map for faba bean. Two F2 populations were analyzed, the most informative of which was segregating for 66 markers. Eleven independently assorting linkage groups were identified in this population. One of the groups contained the 45s ribosomal array and could be assigned to the large metacentric chromosome I on which the nucleolar organizer region is located. This linkage group also contained two isozyme loci, Est and Tpi-p, suggesting that it may share some homology with chromosome 4 of garden pea on which three similar markers are syntenic. Additional aspects of the map and the extent of coverage of the total nuclear genome are discussed.