Abstract: The scattering characteristics of off-axis spherical particles to Gaussian laser beam of TEM00-mode were studied based on the general Mie scattering theory in this paper. According to the expanding form of Gaussian beam in the spherical coordinate system, the limited series solution forms of the expansion coefficient were programmed and calculated. In the case of the scattering of off-axis spherical particles to Gaussian laser beam, the relationship of scattered light intensity with the particle size parameter, refraction rate, scattering angle and relative location of scattering particles were simulated, then the simulation results were discussed and analyzed contrasting with the plane wave scattering patterns. The results show that the scattered light intensity distribution pattern of Gaussian beam is different from the plane wave scattering pattern, but in the case of big beam-waist radius, it has a lot of characteristics in common with the scattering pattern of plane wave.