In this paper, we study the anisotropic diffraction properties of transmission grating based on scaffolding morphology holographic dispersed liquid crystal. Due to the absence of liquid crystal droplet formation within the grating, a simple model is proposed and combined with the anisotropic coupled-wave theory to investigate the diffractive properties. The detailed comparison between experiment and theory indicates that the alignment of liquid crystal molecules in the LC-rich region is along the grating vector.