In this paper, a continuous-wave all-solid-state Nd:YVO4 self-Raman laser in-band pumped by a wavelength-locked laser diode at 878.9 nm is theoretically investigated in detail. Considering the thermal lens effect in the laser crystal, cavity mode parameters are calculated for several output couplers with different radii of curvature, by employing the standard ABCD matrix approach and equivalent G parameter method. The influence of cavity structure on the output characteristic of the Raman laser is investigated by analyzing mode matching between the pump and the fundamental beams, as well as the fundamental intensities in the Raman crystal. This provides theoretical explanations for the experimental results, and based on the analysis above, laser cavity is optimized. Finally, a highest Raman output of 5.3 W is obtained at 1175 nm, corresponding to a diode-to-Stokes optical conversion efficiency of 20%.