The present invention is about a microfluidic chip for rapid detection of different target proteins and a method for using the same. The microfluidic chip utilizes antibody-conjugated magnetic beads to bind to the target proteins to form a magnetic complex, and then use the signal labeled-antibodies that can recognize said magnetic complex. Purifying said magnetic complex by the micro-magnetic field on biochip, and introducing said purified magnetic complex into the fluorescent detection area on the chip to detect the amount of the target protein in said purified complex immediately.