As a member of the tribe Brassiceae, Eruca sativa, although a minor crop worldwide, is considered a valuable genetic resource for cabbage, rapeseed and other Brassica crops. Self-incompatibility (SI) in Brassica has been extensively studied, but information on SI in E. sativa is limited. Of six chemicals used to treat the stigmas to overcome SI in five E. sativa lines, gibberellin was the most effective. As gibberellin is well known for its ability to break dormancy and to promote cell elongation, its effectiveness may help to understand the mechanisms of SI. Urea and ammonium sulphate were also effective. These two chemicals are known to affect protein stability, which may help explain their effects on SI. Although table salt has been reported as being effective in overcoming SI in B. rapa, B. oleracea and B. napu, it was not effective in E. sativa. Sucrose and alcohol also had negligible effect. There was significant variation among the genotypes in SI intensity and response to chemicals, but the genotype–chemical interaction was not significant. The data presented in this paper add to our understanding of SI in E. sativa and may lead to a better use of this genetic resource.