An extended genetic map of sugar beet {Beta vulgaris L.) is presented encompassing 177 segregating markers (2 morphological traits, 7 isozymes, and 168 RFLP markers) on 9 linkage groups. The linkage map comprises 1057.3 cM equivalent to an average genetic spacing of 6.0 cM/marker. The length of individual linkage groups varies between 80.7 (group VIII) and 167.4 cM (group VII). The number of markers per linkage group ranges between 13 and 24. No indication of duplicate regions was found, confirming the true diploid nature of B. vulgaris. Twenty-six markers (15 %) deviated significantly (a = 0.01) from the expected segregation ratio. This distorted segregation was probably caused by Hnkage with lethal genes. Four such genes (designated Let lb. Let 5b, Let 6b, Let 8) could be located at discrete positions due to their absolute Hnkage to skewed RFLP markers. The restorer gene X has been located terminally on linkage group III, 9.6 cM distant from RFLP marker pKP1238.