A device for simultaneously measuring mercury, cadmium, zinc, and lead is provided, including: a gas generating device; a quartz analysis tube connected to the gas generating device, and the quartz analysis tube includes a sample heating zone, a high-temperature packing zone and a quartz collimating tube; an atomic absorption detection device AA1 arranged behind the quartz analysis tube, where the atomic absorption detection device includes an atomic absorption detector, a flame, and a light source; a quartz catalytic tube arranged behind the atomic absorption detection device, where the quartz catalytic tube includes a flame buffer zone and an adsorption packing zone; and an atomic absorption mercury measuring device arranged behind the quartz catalytic tube, where the atomic absorption mercury measuring device includes a mercury enrichment tube, an atomic absorption detector AA2 and an air pump.