Megymenum is a genus of Asian and Australian shield bugs in the family Dinidoridae and typical of the subfamily Megymeninae.

It was erected by Félix Édouard Guérin-Méneville in 1831[2] and species have been recorded from India through to Japan, Indochina, Malesia, New Guinea and Australia.

[1] Species in genus Megymenum have extended or greatly expanded pronotal margins (as in the type species M. dentatum) with a rounded scutellum: characteristic of the Dinidoridae.

In most species the second valvifers are reduced, lightly sclerotised, and fused in the middle.

[3] The following species are currently (as of July 2024[update]) accepted in the genus:[1]