Lead standard interface for collecting electrocardiogram signal and electrocardiograph monitoring device

The invention relates to a lead standard interface which comprises a digital port and an analog port and is characterized in that the analog port respectively comprises 16 analog input ends and analog output ends, wherein the analog input ends are compatible with leads in the amount of one to eighteen; the analog input ends of the analog port are respectively connected with a plurality of electrodes of the leads through lead wires, so that overhead idle ports in the 16 analog input ends are automatically closed when an electrocardiogram analog signal is acquired, and the electrocardiogram analog signal is not acquired from the idle ports; the digital port comprises a plurality of digital input ends and digital output ends; the digital port is electrically connected with the lead wires of different quantity of leads and is used for acquiring digital signals in the lead wires. The invention also provides a lead wire matched with the lead standard interface, an electrocardiogram signal collecting switching module, an electrocardiograph monitoring device and an electrocardiograph monitoring system.