In this paper, we have introduced and studied two-dimensional (P,Q)(P,Q)-Mellin transform which extends the known results of two-dimensional QQ-Mellin transform. We provide its several basic properties, the appropriate convolution, the inversion formula and the Parseval-type relations. Some applications of (P,Q)(P,Q)-Mellin transform have been pointed out in solving integral equations. Finally, a Titchmarsh-type theorem has been proved.