One of the largest genera in the Cruciferae family in Latvia is Sisymbrium L. The genus includes not only native, but also some alien species. The distributions of the Sisymbrium species were reviewed for the first time in the last 50th years in Latvia. The distribution data were compiled from herbarium material, literature and field surveys. An identification key for the Sisymbrium species in Latvia and detailed scientific nomenclature are presented in the current study. In total, seven species of Sisymbrium were found in Latvia — S. supinum L., S. loeselii L., S. polymorphum (Murray) Roth, S. volgense M. Bieb. ex E. Fourn., S. altissimum L., S. orientale L. and S. officinale (L.) Scop. The mainly were recorded in railway verges, roadsides, waste dumps and wasteland. Five species of the genus are alien to the flora of Latvia — S. loeselii, S. altissimum, S. polymorphum, S. orientale, and S. volgense; two are native — S. supinum and S. officinale.
