Low-pass spatial filtering for laser beams plays a key role in improving spatial quality of beams. With the development of high power laser beams, the traditional pinhole spatial filtering becomes a bottleneck to enhance the beam spatial quality, due to its focusing characteristics. Low-pass spatial filtering without focusing is an innovative technique, which can break the bottleneck and improve the spatial quality of beams. Volume grating, multi-layer film, Rugate coating, and photonic crystal have been the main techniques and research focuses to realize the non-focusing spatial filtering for laser beams because of their fine wave vector selectivity. Bragg diffraction of volume grating, constructive and destructive interference of multi-layer and Rugate coatings, and self-collimating of photonic crystal are described to analyze their spatial filtering performance, respectively. The research status of these four techniques for spatial filtering is reviewed. The four techniques can be a substitute for pinhole spatial filtering, especially in the field of high power laser beams.