A physiological signal monitoring device adapted for monitoring a physiological parameter of at least one analyte of a host, comprising a base adapted to be mounted to a skin surface of the host, and provided with a biosensor, the biosensor having a sensing section and a signal output section, the sensing section of the biosensor being adapted to be inserted underneath the skin surface of the host for measuring at least one physiological signal corresponding to the physiological parameter of the host, and outputting the physiological signal via the signal output section; and a transmitter removably coupled to the base, and including a casing that defines an inner space therein for receiving a circuit board and that has a connecting surface facing the base, the connecting surface being provided with a connecting port, the connecting port having a socket that is communicated with the inner space and that is for the signal output section of the biosensor to be removably inserted thereinto, so as to permit the biosensor to be coupled to the circuit board and to output the physiological signal to the circuit board for processing the physiological signal, and an electrostatic-discharge protective unit that is disposed to at least surround the periphery of the socket of the connecting port for bearing and dispelling static electricity when electrostatic discharge occurs. a base adapted to be mounted to a skin surface of the host, and provided with a biosensor, the biosensor having a sensing section and a signal output section, the sensing section of the biosensor being adapted to be inserted underneath the skin surface of the host for measuring at least one physiological signal corresponding to the physiological parameter of the host, and outputting the physiological signal via the signal output section; and a transmitter removably coupled to the base, and including a casing that defines an inner space therein for receiving a circuit board and that has a connecting surface facing the base, the connecting surface being provided with a connecting port, the connecting port having a socket that is communicated with the inner space and that is for the signal output section of the biosensor to be removably inserted thereinto, so as to permit the biosensor to be coupled to the circuit board and to output the physiological signal to the circuit board for processing the physiological signal, and an electrostatic-discharge protective unit that is disposed to at least surround the periphery of the socket of the connecting port for bearing and dispelling static electricity when electrostatic discharge occurs. a casing that defines an inner space therein for receiving a circuit board and that has a connecting surface facing the base, the connecting surface being provided with a connecting port, the connecting port having a socket that is communicated with the inner space and that is for the signal output section of the biosensor to be removably inserted thereinto, so as to permit the biosensor to be coupled to the circuit board and to output the physiological signal to the circuit board for processing the physiological signal, and an electrostatic-discharge protective unit that is disposed to at least surround the periphery of the socket of the connecting port for bearing and dispelling static electricity when electrostatic discharge occurs.