Meinhard Michael Moser (13 March 1924 – 30 September 2002) was an Austrian mycologist. His work principally concerned the taxonomy, chemistry, and toxicity of the gilled mushrooms (Agaricales), especially those of the genus Cortinarius, and the ecology of ectomycorrhizal relationships. His contributions to the Kleine Kryptogamenflora von Mitteleuropa series of mycological guidebooks were well regarded and widely used. In particular, his 1953 Blätter- und Bauchpilze (Agaricales und Gastromycetes) [The Gilled and Gasteroid Fungi (Agaricales and Gastromycetes)], which became known as simply "Moser", saw several editions in both the original German and in translation. Other important works included a 1960 monograph on the genus Phlegmacium (sometimes considered part of Cortinarius) and a 1975 study of members of Cortinarius, Dermocybe, and Stephanopus in South America, co-authored with the mycologist Egon Horak.