A combustion device includes: a liner in which a combustion chamber is formed inside a side wall portion; a burner that injects fuel into the combustion chamber; an air introduction portion that introduces air into the combustion chamber; a separation wall portion provided on a radially outer side of the liner with respect to the side wall portion and forming an inner flow path communicating with the air introduction portion between the separation wall portion and the side wall portion; an outer wall portion provided on a radially outer side of the liner with respect to the separation wall portion; a plurality of communication holes formed in the separation wall portion in such a manner as to be separated from each other in a central axis direction of the liner; and a partition wall partitioning the inner flow path in the central axis direction of the liner.