Aegista tenuissima is a species of air-breathing land snails, a terrestrial pulmonate gastropod in the family Camaenidae.

The thin shell exhibits a delicate, lightweight structure, taking on a disc-like form with a gently curved spire and distinct angular periphery.

The surface of the shell boasts a glossy sheen, adorned with fine, irregular striations and subtle spiral patterns.

The body whorl descends slightly at the front and flattens beneath the peripheral angle before rounding off at the base.

Encircling this opening is a narrowly reflexed peristome, delicately thin, with a faint white thickening present within.