Pattern formations in dielectric barrier discharge in argon at atmospheric pressure under different discharge conditions are investigated. Patterns undergo the transition sevies of hexagonal-square-square with glow background-hexagonal with glow background as the applied voltage is increased, and the spatial wavelength and the filament density change also. When the glow background appears under a certain discharge condition, the spatial wavelength and the filaments density remain constant and the number of discharge pulses of each filament in half cycle changes from one to two.