The invention discloses a detection device and method for a diabetic nephropathy biomarker. The device comprises a test strip slot, a scanning unit, a camera shooting unit, a communication unit and abiomarker detection system. The test strip slot is used for installing a colloidal gold test strip for detecting the biomarker, and the colloidal gold test strip comprises a two-dimensional bar code and a biomarker detection band. The device is used for controlling the scanning unit to scan the two-dimensional bar code to obtain two-dimensional bar code information and controlling the camera shooting unit to capture a detection result image of the biological marker from the biomarker detection band; the type of the biomarker is identified according to the two-dimensional bar code information;the gray value reacting a colored-zone region in the detection result image is compared with a standard product gray value to obtain a content detection result of the biomarker; and the type and the content detection result of the biomarker are sent to a health management cloud platform for storage. According to the device and the method in the invention, the content of the diabetic nephropathy biomarker can be accurately analyzed, and detection result deviation caused by subjectivity or errors is avoided.