In the anatomy of turtles (including tortoises and terrapins), the plastron is the smaller, flatter part of a turtle shell, and together with the carapace is an integral part of a turtle's skeleton. In an ordinary turtle crawling in prone posture, the plastron is the bottom part of the shell.

In a humanoid mutant turtle, the plastron comprises the turtle's chest and abdominal region on the anterior/front, and depending on the comic or television series (or artist), can also appear muscular. It usually appears to be a lighter yellowy color, compared to the darker brown of the carapace in the back.

See also