A watch-typed heartbeat sensing device includes a casing which defines a hollow space for the mounting of a circuit board provided with a plurality of contacts and a control circuit. The casing has two ends, a first end being mounted with a first pair of conductors which includes an inner plate and an outer plate, the two plates respectively connecting to a first and second contacts of the circuit board, a second end being mounted with a second pair of conductors which comprises an inner plate and an outer plate, the two plates respectively connecting to a third and fourth contacts of the circuit board. When a user puts on the heartbeat sensing device, the inner plates contacts wrist of the user, and when he puts his other hand on the heartbeat sensing device and touches the outer plates, two pairs of heartbeat signals are generated and transmitted to the circuit board, so that the heartbeat of the user is calculated and displayed.