A safety device for a motorized fitness equipment includes a socket provided with two first and two second slots; a conductive magnet on bottom of each first slot; and a metal clip in each second slot; a conductive device containing two separate conductive terminals each having a first and a second extensions; the first extension when connected to the first slot being electrically connected to the magnet; and the second portion being inserted into the second slot and held by the metal clip to constitute a circuit breaker by having the socket to combine with or clear away from the conductive device.