The Rho-kinase (ROCK) family members, consisting of ROCK1 and ROCK2, are serinethreonine kinases that are activated by small GTPases. ROCKs play central roles in the actin cytoskeleton organization and regulate a wide range of fundamental cellular functions, such as apoptosis, inlammatory responses, cell contractility, adhesion, migration, motility, proliferation, phagocytosis, and apoptosis. Accumulating evidence from basic and clinical studies supports the concept that ROCK plays important roles in many diseases and could be a potential therapeutic target for diverse disorders, including cardiovascular, neurologic, metabolic, autoimmune disorders, and cancers. Although there are only limited numbers of published studies related to ROCK polymorphisms in humans, the contribution of the genetic studies related to ROCK variants to the disease states is emerging. Identifying mutated genes or associated polymorphisms and evaluating their potential risks are important steps for understanding the genetic components and pathogenesis of diseases. Identiication of functional mutations or polymorphisms could potentially help in the development of novel ROCK-speciic therapies in related disease states.