| Dorcus rectus | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Clade: | Pancrustacea |
| Class: | Insecta |
| Order: | Coleoptera |
| Suborder: | Polyphaga |
| Infraorder: | Scarabaeiformia |
| Family: | Lucanidae |
| Genus: | Dorcus |
| Species: | D. rectus |
| Binomial name | |
| Dorcus rectus (Motschulsky, 1857) | |

Dorcus rectus, the little stag beetle, is a species of beetles in the family Lucanidae. It can be found in China(Liaoning), Korea, Japan, Russia. These beetles have a distinctive red shell that separates them from Dorcus curvidens. Males of this species have been observed to have mandible trimorphism, a characteristic that has only been described in two species of Lucanidae—with the other one being Odontolabis cuvera—"and a small number of other invertebrates" as of 2017. The mandibles are used by males as weapons.