It is described an emergency device (100) for divers comprising a watertight case (101) structured to assume a submerged position and an emerged position. The watertight case includes: a depth sensor (102) configured to determine a depth value associated with the submerged position assumed by the emergency device when a user activates an emergency procedure; a positioning device (103) configured to determine a geographic position, including latitude and longitude, assumed by the emergency device (100) in the emerged position; a GSM or satellite telephone transmitter/receiver (104) configured to transmit an emergency message comprising said depth value and said geographic position.