deuteromycetes, fungi (kingdom Fungi) in which a true sexual state is uncommon or unknown. Many of these fungi reproduce asexually by spores (conidia or oidia) or by budding. Conidial stages are similar to those in the phylum Ascomycota, but those of some species show affinities to lower (primitive) fungi and the phylum Basidiomycota.

The Deuteromycota is a heterogeneous group of unrelated species in which sexual reproduction has never been observed. Since mycologists refer to the "perfect phase" of a life cycle as the phase in which sexual reproduction occurs, these fungi are often referred to as imperfect fungi.

Commonly called molds, Deuteromycetes are "second-class" fungi carrying no sexual state in their life cycle, reproduced only by producing spores via mitosis. This state of asexual fungi is called Anamorph.

Species of the Deuteromycota (deuteromycetes), also known as the imperfect fungi or mistosporie fungi, are among the most economically destructive group of fungi. These fungi cause leaf, stem, root, fruit, and seed rots; blights; and other diseases.