A LD side-pumped 589 nm small-scale all-solid-state laser with an intra-cavity sum-frequency structure was developed and the experiments for exciting the brightness of a sodium guide star by the laser were described. The numerical simulation method was employed to analyze and design the cavity length and the position of a sum-frequency crystal, and it shows a smaller size and higher conversion efficiency. A synchronous power system in time domain was developed to compensate the delay between pulses of the two fundamental lasers. Special films were coated on the sides of the splitter mirror to obtain linear polarized laser as well as to increase the conversion efficiency and the thermal stability. Moreover, etalons and special coating methods were employed to suppress the oscillation of 1 338 nm spectral line. Finally, a dedicated launch telescope and a receive system were used for the generation and observation of sodium guide star. Test results show that the laser offers an output power more than 8 W, a repetition frequency of 5 kHz and the linewidth less than 3.5 GHz, meanwhile, its conversion efficiency is up to 2% corresponding to the 808 nm pump power. Under the sky background light of Changchun, the brightness of the guide star excited by the laser in winter experiments is about 10 Mv.