Particle acid, as a slow-acting system, offers the advantage of effectively penetrating deep into carbonate reservoirs during the acidizing process. Clarifying the acidification mechanism of solid particle acid in carbonate reservoirs holds great importance for optimizing and assessing acid types. As a result, this paper introduces a new mathematical model capable of describing the acidification process of solid carbonate particles. It also examines the effects of various factors such as injection rate, particle acid release rate, and acid concentration on the acidification process. The research reveals that as particle acid concentration and injection rate increase continuously, the wormhole's length and width noticeably expand, the pressure difference between the inlet and outlet decreases, and the time for reservoir penetration decreases. The release rate of particle acid influences the etching pattern. When the particle acid release rate is low, the dissolution occurs uniformly, but with a high release rate, a wormhole formation is observed. The corrosion amount varies over time, demonstrating an S-shaped trend at low dissolution rates and an L-shaped trend at medium and high dissolution rates.