The Mindlin-type model is used for describing the deformation waves in microstructured solids. The 2D evolution equation (one-wave equation) is derived based on hierarchical governing equations by using the perturbation method. This equation is of the Zabolotskaya–Khokhlov-type and is integrated numerically under localized initial conditions (related to appropriate boundary value problems) by the FFT-based pseudospectral method. Analysis of results demonstrates that the derived evolution equation is able to grasp essential nonlinear effects of microinertia and elasticity of microstructure. Such an equation can be used in the NDT of microstructured materials in order to model wave beams generated by ultrasonic transducers.