Sensors have been widely recognized in matrix metalloproteinases(MMP)detection for their high sensitivity,simplicity,speed and easy in vivo and vitro detection.The design thought of existing sensors is based on the structure of MMP-9 molecule or the enzyme activity to output different signals in response to sensing.In this paper,we summarize the current research status and difficulties of MMP-9 sensing detection technology,and further discuss the development prospects of MMP sensor,which will provide a reference for the detection of MMP-9 and other good biological target molecules.