Didogobius splechtnai is a species of goby native to the Mediterranean Sea along the coasts of Spain and Italy where they inhabit caves with sandy substrates at depths from 7 to 11 m (23 to 36 ft). This species can reach a standard length of 2.3 cm (0.91 in). The specific name honours Professor Heinz Splechtna (1933-1996), a marine biologist at the University of Vienna.