Temporal dominance of sensation (TDS) combined with time-intensity (TI) method was used to evaluate acidity changes and sensory changes of mountain wines before and after acid reduction, such as mildness, refreshingness, Irritation, roughness, and bleakness. The acidity intensity of mountain wine before and after acid reduction was evaluated by TI method, and results showed that the acid intensity of mountain wine was low after acid reduction. In the process of 60s evaluated by TI method, the acidity intensity of mountain wine before and after acid reduction showed a decreasing trend. The TDS method was used to evaluate the sensory changes of mountain wines before and after acid reduction. With the increase of tasting time, the predominant acidity in the acid-reducing foreland wines was irritant. The dominance rate showed a decreasing trend, and other acid sensations were masked and the taste was lacking in coordination. After acid reduction, the tenderness advantage of the acidity of the mountain wine increased first and then decreased. The advantage of refreshingness first increased and then decreased and then remained basically unchanged. The irritative advantage rate gradually decreased, the dominance advantage decreased first, then rose and then decreased, and the oligomatic advantage was obtained. The rate gradually increased. After deacidification, the mountain wine was more coordinated and palatable. Therefore, the TDS combined with TI method can effectively evaluate the acidity intensity and different acid-sensing properties of mountain wine before and after acid downgradation over time, which is of theoretical significance for deacidification of mountain wines.