A high-power quasi-continuous microsecond pulse sodium guide laser was generated by extra-cavity sum frequency of Nd: YAG 1064 and 1319 nm spectral line lasers in a Lithium Borate (LBO) crystal. The three wave coupling equations of the sum-frequency process were simulated by the improved Euler method, and the waist size of fundamental light and the length of LBO crystal were optimized. To improve the sum frequency efficiency, the spatial mode matching and time domain pulse synchronization of two fundamental lasers were realized by the beam shaping of image propagation and the precise control of trigger delay. The laser outputs were researched ,and the results show that the 589 nm laser outputs with the powers of 53, 42.6, 27 and 22 W are obtained under the conditions of 500, 600, 800 and 1000 Hz, and the corresponding sum-frequency efficiencies are 21.8%, 20.3%, 16.9 % and 16.3%, respectively. Moreover, the beam quality factor of M2 is 1.32 and the pulse width is 100 μs at the maximum power of yellow light. A control system compound by a PZT and a stepper motor was used to stabilize the frequency, and results indicate that the frequency fluctuation is in the range of ±0.2 GHz, which ensures that the wavelength of yellow light is within the D2a absorption spectrum of sodium atom. The research results iprovide a technologic support for generating 50 W high-power quasi-continuous microsecond pulse sodium guide lasers.