Vertical Cavity Surface Emitting Laser (VCSEL) array has the advantages of high integration, high modulation bandwidth, high output power, fast response and individual addressing, so it is widely used in parallel optical interconnection, 3D recognition and sensing, high resolution printing and other fields. With the development of science and technology, the quality of laser array light source is required to be higher. For example, in order to suppress the speckle phenomenon and realize confocal micro-interference detection with high spatial resolution and high contrast, the VCSEL array light source is required to have flat top beam output with low spatial coherence. In the optical capture and microoperation of biological cells, in order to produce an optical trapping array effect, the beam of the VCSEL array needs to be regulated into Laguerre-Gaussian hollow circular distribution. The beam distribution and spatial coherence of VCSEL and its array have attracted more and more attention. Similarly, in free-space optical communication, the laser beam distribution and spatial coherence are closely related to the disturbance effects such as beam broadening, spot drift and intensity scintillation transmitted in a turbulent atmospheric scattering medium. It is of great significance to research the spatial coherence and light field distribution of array light source to optimize their transmission characteristics. In this paper, the spectrum of the VCSEL array is measured and the light field distribution of the VCSEL array is researched. At the threshold current, the VCSEL array is emitted as the fundamental mode, and the energy of the fundamental mode beam is distributed in the center of the luminous aperture and the light spot divergence degree is small. At this time, the far field of the array is a circular light spot formed by the superposition of the light beams of each luminous unit, and the light field is Gaussian distribution. With the increase of injection current, the high-order mode of the VCSEL array beam gradually appears. Because the energy of the high-order mode is mainly concentrated at the edge of luminous aperture, the light field of the VCSEL array is Laguerre-Gaussian hollow circle. Furthermore, the experimental device of VCSEL array beam space transmission was built. The propagation characteristics of a standard coherent light source and VCSEL array beam with different coherence were compared in the atmospheric turbulent scattering medium. The VCSEL array beam is collimated out through the lens, after the beam splitter through the two-hole interference, the interference fringes are recorded by Spiricon SP920s beam analyzer, and the spatial coherence of the beam is obtained by calculating the contrast of the interference fringes. At the same time, the randomness and inhomogeneity of atmospheric turbulence are simulated by a scattering medium. The beam analyzer is used to record the far-field spot radius and light intensity before and after VCSEL array beam transmission, and the beam expansion rate and light intensity attenuation rate in the transmission process is calculated. Experiments show that compared with the standard coherent light source, the VCSEL array beam has smaller spot diffusion and lower light intensity attenuation when propagating in a turbulent atmospheric scattering medium. As the spatial coherence of the VCSEL array decreases from 0.695 to 0.608, the spot spread rate decreases from 8.6% to 3.4%, and the intensity attenuation rate decreases from 24.9% to 15%. VCSEL array beams with relatively low spatial coherence show better propagation characteristics, which has important guiding significance for the application of VCSEL array light source in the fields of free space radar detection and optical communication.