The invention discloses a monitoring system of an omnibearing distributed coal-gangue-mountain spontaneous combustion prevention and a method thereof. Through constructing an omnibearing distributed monitoring system, an internal temperature of a coal gangue mountain is monitored in real time, a corresponding technology parameter is acquired and coal-gangue spontaneous combustion is prevented. In the invention, through using a novel sensing test technology (a distributed fiber sensing test technology), a test device is improved and a set of complete coal-gangue-mountain spontaneous combustion prevention test method is acquired; and by using the acquired technology, good safety guarantee can be provided for aspects of coal-gangue spontaneous combustion prevention and fire extinguishing processing.