To provide a safety system for boom working vehicle, which can improve the safety at the time of operating a boom even in a case where a moment limiter is not provided.
A controller 23 detects whether a boom 10 is turned right or left on the basis of the information from a turning angle detecting unit 22. When a grounding reaction of both a front and a rear jacks of a side, which is not detected, at zero is detected or a grounding reaction of at least one of the front and rear jacks of a side, which is detected, at zero detected, the operation of a turning cylinder 16 for operating a boom 10 in a direction for increasing an overturning moment Mt and the operation of a boom hoisting cylinder 17 are regulated, and the alarm operation for displaying an alarm with an alarm lamp 24 or buzzing a buzzer 25 is performed.
SASAKI SATOSHI
ISHII KATSUO
