To achieve real time processing for volume rendering, it is necessary to employ parallel processing techniques. Therefore, a ray casting wavefront architecture is proposed. The architecture offers the following advantages. By a special memory organization, the processor array can perform fast rotation along x, y, z axes without incurring costly memory transformation. The projection phase and post-projection phase are assigned to different processors and a significant time-saving can be achieved by the pipelining technique. In the proposed architecture, the projection processors can skip the transparent region and step computation when further computation does not affect pixel values any more, e.g., the rays reach opaque surface. Finally, according to the VHDL simulation result, the speedup of the wavefront architecture over several SIMD designs (including CM2 and the Princeton Engine) is about 200% under normal condition.