A touch display panel, including a pixel circuit substrate, a color filter substrate, and a display medium layer, is provided. The pixel circuit substrate includes pixel structures, data lines, touch sensing electrodes, touch signal lines, and at least one test circuit. Each pixel structure has an active element and a pixel electrode. The data lines are electrically connected to active elements. The touch sensing electrodes are overlapped with pixel electrodes. The touch signal lines are electrically connected to the touch sensing electrodes. The test circuit is electrically connected to at least part of the touch signal lines or the data lines and includes a peripheral line and first and second test pads. The first and second test pads are respectively disposed on a first side and a second side of a display area. The display medium layer is disposed between the pixel circuit substrate and the color filter substrate.