A safety device for use in a bathroom includes a float and a detecting and controlling assembly. The float has a housing defining a receiving space. The detecting and controlling assembly is mounted in the receiving space. The detecting and controlling assembly includes an inclination detector, a processing unit, and a transmitting unit. The inclination detector and the transmitting unit are electrically connected to the processing unit. The inclination detector is adapted to detect a posture of the float and adapted to send a detection signal indicative of the posture of the float to the processing unit. The processing unit processes and analyzes the detection signal and sends out an emergency signal through the transmitting unit.