The present invention relates to a technology field of a printed circuit board, and more particularly to a connection structure of a printed circuit board and a connection method thereof. The connection structure of the printed circuit board of the present invention comprises a first and second printed circuit boards. One end of the first printed circuit board disposes a receiving portion. One end of the second printed circuit board disposes a protruding portion. The shape of the protruding portion is corresponding to that of the receiving portion. When connecting the first and second printed circuit boards, the protruding portion is engaged with the receiving portion so that realizing a physical connection. The connection structure and the connection method may reduce the product cost. Moreover, the printed circuit boards connected by the solution of the present invention can be conveniently mounted and dismounted to simplify the operation.