The invention relates to a fire prevention technology for a flexible direct-current converter substation IGBT valve hall, in particular to a fire prevention measure tripping mode for a flexible direct-current converter substation IGBT valve hall. Concurrence of two types of warning signals, namely, extremely-early smoke warning signals and ultraviolet (infrared) detection warning signals serves as a criterion for stopping a flexible direct-current system. On one hand, as long as one of all extremely-early smoke detectors in the valve hall detects smoke warning and meanwhile one of all ultraviolet probes detects arc light, a logical control and protection system is allowed to perform tripping; on the other hand, if smoke is detected at an air inlet, a first logical judgment unit is locked, at the moment, if two or more ultraviolet probes of an ultraviolet detection system give warning at the same time, the control and protection system is allowed to perform tripping on an outlet, and besides, a tripping signal is directly transmitted to a redundant direct-current control and protection system of a converter station without passing through a central warning device of a fire warning system. The fire prevention measure tripping mode has the advantages that system shutdown can be timely and effectively performed, equipment damage can be avoided, and safe and stable operation of the converter station can be ensured.