The list of marine heterobranch gastropods of South Africa is a list of saltwater mollusc species that form a part of the molluscan fauna of South Africa. This list does not include the land or freshwater molluscs. This is a sub-list of the list of marine gastropods of South Africa, which is in turn a sub-list of the list of marine molluscs of South Africa. Heterobranchia, the heterobranchs (meaning "different-gilled snails"), is a taxonomic clade of snails and slugs, which includes marine, aquatic and terrestrial gastropod mollusks.