A display device and a display driving circuit with electromagnetic interference suppression capability are provided. The display device includes a substrate, an active matrix, a display driver and a thin-film transistor (TFT) conditioning circuit. The active matrix disposed on the substrate includes multiple data lines, multiple gate lines and multiple pixels. The data lines intersect with the gate lines. The pixels are coupled to intersections of the data lines and the gate lines. The display driver disposed on the substrate generates signals for driving the data lines and/or the gate lines in response to a conditioned serial data clock. The TFT conditioning circuit disposed on the substrate is coupled to the display driver. The TFT conditioning circuit includes one or more TFTs, and attenuates an amplitude of a serial data clock in response to a predetermined gate bias to provide the conditioned serial data clock to the display driver.