Hydroxamic acid derivatives are potential histone deacetylase inhibitors, and several hydroxamic acid-based histone deacetylase inhibitors have already been used clinically as potent anticancer agents, so hydroxamic acid derivatives are useful scaffolds for the development of novel anticancer agents. Hybridization of hydroxamic acid moiety with other anticancer pharmacophores can overcome drug resistance and improve the specificity, so rational design of hydroxamic acid hybrids may provide valuable therapeutic interventions for the treatment of cancers. The purpose of the present review article is to update the current developments in hydroxamic acid hybrids with an emphasis on anticancer activity, structure-activity relationships, and mechanisms of action.