Due to inhomogeneous spatial distribution and large divergence angle of the laser diode array (LDA), LDA is inconvenient for end-pumping solid-state lasers, and the output beam reshaping and coupling is required. A coupling system for end-pumping solid-state lasers is designed with Zemax. The system is composed of a fast axis collimating lens and a lens duct. The relationship between the coupling efficiency and the characteristic parameters of the lens duct is studied. The optimal coupling system parameters are obtained by ray tracing. The final designed lens duct is 22 mm long, the input surface size is 12 mm (fast axis) ×9 mm (slow axis), the output surface size is 3.5 mm×3.5 mm, the radius of curvature is 14 mm, and the coupling efficiency can reach 90.7%. The beam divergence angle at 1 mm away from the lens duct is 0.38 mrad for fast axis and 0.02 mrad for slow axis. This system can make the pumping beam and the oscillating beam match well.