The beam nature of the flattened radial Gaussian laser beam array in a turbulent atmosphere is investigated based on the extended Huygens-Fresnel integral and Wigner distribution function for turbulence conditions. Analytical propagation formula for the propagation factor ( M2 factor) are derived and numerical examples are illustrated. The results show that the propagation factor of the flattened radial laser beam array in turbulent atmosphere increases when propagation distance and turbulent constant increase and beam width decreases. The propagation factor of the flattened radial laser beam array does not change at first, then it decreases, and it is invariant in the end when the flattened radial laser beam array’s orders are fixed and its numbers increase. The propagation factor of the flattened radial laser beam array does not change, then it decreases, maintains a fixed value finally when the flattened radial laser beam array’s numbers are fixed and its orders increase. The propagation factor is unchanged as the flattened radial laser beam array are propagating in free space.