<p>To address challenges such as slow computation and complex modeling in particle-reinforced composites, the Voronoi cell finite element method (VCFEM) is extended to the viscoelastic regime. Numerical simulations of mesoscale models with varying particle densities under displacement boundary conditions are conducted. Based on viscoelastic material behavior, a time-domain adaptive algorithm is developed to construct a modified complementary energy functional that captures material viscoelasticity using the generalized Maxwell model. This leads to the formulation of a viscoelastic VCFEM based on an reciprocal stress function. Results demonstrate that VCFEM effectively characterizes the mechanical response of viscoelastic materials, validates its scalability for multi-particle-reinforced composites, and indicates broad application potential.</p>