As an useful perspective,the NATM has gone into many hands of the tunnel and underground structure designs and constructions.But the supporting time,which determines the tunnel's support quality,is usually determined by the engineer's experience.What's more,different engineers have different decisions on the supporting time,so the construction project quality would vary greatly.In this thesis the neuro-fuzzy inferential system was set up to gain the supporting time,which can make a good use of the experience of the engineering projects.The result suggests that this system has a good accuracy and is useful in the engineering practice.