Prepositional case is a grammatical case that marks prepositions. In some languages, e.g. English and Spanish, all prepositions take a single case; in others, e.g. Latin and Russian, multiple cases can take prepositions, and the same preposition can take various cases with constrasting meanings.

In Russian, the term "prepositional case" (predlozhniy padezh) is used as the name of the locative case, as it can only occur with a preposition. The case cannot occur independently, with locative meaning or otherwise, and it is governed by some prepositions which lack any spatial meaning.