Amastra tenuilabris is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusc in the family Amastridae.

[1] Subspecies: Amastra tenuilabris rubicunda (Baldwin, 1895) The length of the shell attains 15 mm, its diameter 8 mm The shell is dextral, ovate-conic, and slightly dull, marked with somewhat coarse growth striations.

It is white, overlain by a tawny epidermis that tends to wear away below the suture on the body whorl.

The peristome is thin, and the columella is straight, featuring a small central fold.

[2] This species is endemic to Hawaii, occurring on Oahu island.