A safety design method for an electromagnetic flowmeter is provided. The method includes following steps: providing an electromagnetic flowmeter including a measuring pipeline allowing a working fluid to flow through therein and a power supply module; defining a first explosion-proof hazardous area for containing the power supply module in the electromagnetic flowmeter; defining a second explosion-proof hazardous area for containing the measuring pipeline in the electromagnetic flowmeter; and separating the first explosion-proof hazardous area from the second explosion-proof hazardous area.