With the use of fundamental wave of high power laser diode end-pumped Nd:YAG and the intra-cavity second-harmonic generation (SHG) effect and sum-frequency generation (SFG) effect of nonlinear optical crystal, a multi-wavelength yellow laser with simultaneous multi-second-harmonic outputs is proposed. By using 1112.1, 1115.9, 1122.7 nm outputs of Nd:YAG as fundamental waves, and selecting LBO and BIBO for nonlinear frequency conversion, three SHG lights and three SFG lights are obtained at the same time. The simultaneous stimulated transition of fundamental frequency lights and the phase matching nonlinear frequency conversion are analyzed theoretically. Experimental results and theoretical analysis show that when fundamental waves′ performances are relatively close to each other, reasonably choosing nonlinear crystals with good performance for frequency doubling and sum frequency of wavelengths at the same time is a practical method to realize all-solid-state multi-wavelength laser. Reasonably designing laser resonator can improve the stability of the laser.