Summary: For \(\rho\in[0,1)\) and \(\varepsilon\in(0,1)\), we investigate the uniform attractors of a 3D non-autonomous Navier-Stokes-Voight equation with singularly oscillating forces \[ \begin{aligned} & u_t-\nu\Delta u-\alpha^2\Delta u_t+(u\cdot\nabla)u+\nabla p=f_0(t,x)+\varepsilon^{-\rho}f_1(t/\varepsilon,x),\;x\in\Omega, \\ & \nabla\cdot u=0,\;x\in\Omega,\\ & u(t,x)|_{\partial\Omega}=0,\\ & u(\tau,x)=u_\tau(x),\;\tau\in \mathbb R,\end{aligned} \] together with the averaged equations (corresponding to the limiting case \(\varepsilon=0)\) \[ \begin{aligned} & u_t-\nu\Delta u-\alpha^2\Delta u_t+(u\cdot\nabla)u+\nabla p=f_0(t,x),\;x\in\Omega, \\ & \nabla\cdot u=0,\;x\in\Omega,\\ & u(t,x)|_{\partial\Omega}=0,\\ & u(\tau,x)=u_\tau(x),\;\tau\in \mathbb R.\end{aligned} \] Under suitable assumptions on the external forces, we obtain the uniform boundedness of the related uniform attractor \({\mathcal A}^\varepsilon\) of the first system, and the convergence of \({\mathcal A}^\varepsilon\) to the attractor \({\mathcal A}^\varepsilon\) of the second system as \(\varepsilon\to 0^+\).