Guevara elevated guerrilla warfare to the height of political philosophy, proposing that it serves as a "catalyst" for revolution—a core viewpoint that constitutes the pillar of his guerrilla thought system. This paper systematically elaborates on Guevara's theoretical framework regarding the "catalytic" role of guerrilla warfare, focusing on three core dimensions: first, analyzing the guerrilla army as the main implementer of the "catalyst," revealing its multiple roles and inherent characteristics as the vanguard of the people's armed forces, social reformers, and prototypes of the "new man"; second, sorting out the three developmental stages of guerrilla warfare as a catalytic process—namely the nomadic stage, the honeycomb stage, and the urban stage—demonstrating its dynamic trajectory from germination and expansion to seizing political power; finally, delving into the specific mechanism of action of the "catalyst" in revolution, analyzing how it constructs a bridge between objective conditions and subjective consciousness through the interaction of military and political affairs, catalyzing the maturity of revolutionary conditions and the awakening of the masses. By sorting out and integrating Guevara's original texts, this paper logically interprets his theory of guerrilla warfare as a "catalyst" layer by layer, so as to reveal its theoretical connotation and practical path.