The present disclosure provides a display apparatus capable of configuring layout information including rotation information of a display without user setting when a plurality of display apparatuses are connected, a method of controlling the display apparatus, and a display system. The display apparatus includes a display; a communication interface configured to communicate with at least one other display apparatus; and a controller configured to calculate position information of a display apparatus, to receive position information including rotation information of the at least one other display apparatus through the communication interface, and to output an output image signal to the display based on the position information of the display apparatus and the position information of the at least one other display apparatus.