Entoloma moongum is a South Australian species of fungus in the large agaric genus Entoloma (subgenus Leptonia).

It was described as new to science by mycologist Cheryl Grgurinovic; the original holotype collections were made from Belair National Park in the 1930s by John Burton Cleland, who erroneously referred the fungus to Leptonia lampropus (now Entoloma lampropus).

[1] The fruitbody has a dark brown to purplish brown cap up to 19 mm (0.75 in) in diameter with a surface that is finely fibrillose, and a cap cuticle consisting of narrow hyphae.

The spores measure 9.6–13.6 by 5.6–8.4 μm and have 5–6 blunt angles.

The specific epithet derives from the Aboriginal word moonga, meaning "dark".