The invention discloses a peritoneal drainage early warning device, which comprises a drainage chamber with scale lines on an inner wall, wherein the inner wall of the drainage chamber is provided with a vertical communication tube, and a plurality of L-shaped chromoscopes are arranged perpendicular to the vertical communication tube; chromogenic test paper is inlaid in the chromoscopes; a top cover is arranged on the top of the drainage chamber; the top cover is connected with an upper drainage cover and a lower drainage cover which can rotate relative to each other; a drainage hard pipe penetrates through the center of the upper drainage cover and the center of the lower drainage cover; one end of the drainage hard pipe extends into the drainage chamber and the other end of the drainagehard pipe is connected with a drainage hose; a negative pressure pipe for connecting with a vacuum extractor further penetrates through the upper drainage cover; and the lower drainage cover is provided with a negative pressure pipe connector matching with the negative pressure pipe. The peritoneal drainage early warning device can selectively communicate with the vacuum extractor, firstly performs economic treatment when causing discomfort, and can also judge different liquid levels with the chromogenic test paper. The device effectively improves the use experience of a patient and brings convenience to both the patient and a caregiver.