<p>This paper presents an electromechanical coupling hybrid finite element method (EM-HFEM) for solving the stress and electric displacement in piezoelectric particulate composites. The work proposes an electromechanical coupling polygonal hybrid element model, where the stress field and electric displacement field are independently assumed within the element domain, while displacement and potential are independently assumed on the element edges. By introducing displacement and potential as Lagrange multipliers into the complementary energy functional, the generalized surface force equilibrium conditions at element boundaries are relaxed, thereby establishing a modified complementary energy functional. Consequently, a four-variable function involving stress, electric displacement, displacement, and potential is proposed. The stress and electric displacement in the domain satisfy the equilibrium equations a priori, thereby constructing higher-order stress and electric displacement functions. Displacement and potential are interpolated exclusively on the element boundaries. The proposed hybrid element eliminates shape function requirements and applies to arbitrary polygonal elements, enabling the combination of polygonal-quadtree meshes. The accuracy of the polygonal-quadtree mesh element is validated through comparisons with pure quadtree mesh elements. Numerical examples against traditional finite element methods demonstrate the precision advantages of EM-HFEM in distorted meshes and its computational efficiency in analyzing piezoelectric particulate composites when combined with polygonal-quadtree meshes.</p>