In this article, wave propagation characteristics of a size-dependent laminated composite nanostructure coupled with a piezoelectric actuator (PA) is investigated. In order to consider the effects of small scale, the governing equations of the laminated composite nanostructure coupled with PA are derived using Hamilton's principle based on the nonlocal strain gradient theory (NSGT). The differential equations of motion are solved with the assistance of the analytical method. Afterward, a parametric study is carried out to investigate the effects of the PA thickness, wave number, angular velocity and the ply angle on the value of phase velocity. The results show that the ply angle plays an important role on phase velocity changes of the laminated composite nanostructure by increasing wave number. It is also observed that by assuming a constant field of phase velocity, increase in the thickness of PA leads to increase in the critical value of external voltage which is associated with increase in the stability of the laminated composite nanostructure coupled with PA.