Arbuscular mycorrhizal fungi (AMF) form symbiotic relationships with plant roots and produce spores that play a crucial role in their survival and identification. These spores are multiwall asexual structures with diverse morphological traits, including variations in size, shape, color, and wall composition. Understanding these characteristics is essential for AMF taxonomy and ecological studies. This chapter explores the five main spore morphotypes—acaulosporoid, entrophosporoid, gigasporoid, glomoid, and radial-glomoid—highlighting their formation processes and taxonomic significance. Additionally, the organization of spore walls is examined, emphasizing the transition from traditional classifications to more detailed structural analyses that consider multiple layers. The complexity of AMF taxonomy is further discussed, focusing on the influence of environmental factors, spore plasticity, and methodological challenges. Practical guidelines for extracting, characterizing, and documenting AMF spores are provided, offering valuable insights for researchers investigating fungal diversity and plant–fungal interactions.