Abstract: Recently,one important method for optical manipulation is to realize the discontinuity response of phase with the array of different V-shaped gold antennas or dielectric particles,which are elaborately designed to obtain the same phase increment between adjacent antennas and phase coverage of 2π in one lateral period of the antenna array. However,these artificially engineered nanostructures have thus far been limited to operate on light beams propagating out-of-plane. The in-plane operation is critical for on-chip photonic applications. Here,we demonstrate an anomalous optical manipulation of a light beam propagating along the plane,by designing a thin dielectric array of high permittivity nano-posts. The underneath physics is that the particular scattering property of the nano-posts in the line which alters theoutgoing wavefronts. These anomalous phenomenons paves a new way for on-chip beam control for optical communications.