Didogobius splechtnai sp. nov. is decribed from seven specimens collected at the Balearic Island Ibiza, western Mediterranean. The new species is assigned to Didogobius on the basis of the almost complete agreement in the pattern of cephalic sensory papillae. It differs from all other species of the genus in the combination of squamation, lateral-line system and fin features. Diagnostic values for the new species are D2 I/9-10, A I/9, P 15-16 and LI 28-30. This small cryptobenthic gobiid fish was found in submerged caves at a depth of 7-11 m. A key to the species of the Mediterranean and eastern Atlantic genus Didogobius is provided.