Philautus hosii is a species of the lowlands and hilly regions. It is a medium-sized frog (males up to 49 mm, females to 63 mm). 

The snout is sharp-edged. Coloration is in shades of brown with a dark X between the shoulders and dark round dots on the flanks of most specimens. The iris is yellow to green. The skin is finely granular dorsally.

Inger & Stuebing (2005) mentioned that they have seen eggs on vegetation overhanging streams that they think belong to this species. This could mean that this species may have free swimming larvae.