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

Its surface is glossy, adorned with delicate, closely spaced thread-like rib-striae aligned with the growth lines.

The shell's coloration is a rich dark chestnut-brown, decorated with light brown zigzag or undulating lines and markings.

The aperture is oval and slightly oblique, with a livid white interior that subtly reveals the brown exterior coloration.

The axis is imperforate in the adult and later neanic stages, but in the half -grown shell there is a rather widely open umbilicus, width about 1 mm.