Abstract: A protective boot for pet animals has a sole member and a flexible upper attached together around their corresponding front and side edges, with the back of the boot left open for direct easy paw insertion. The upper is designed to be folded over on itself, or pleated, longitudinally to bring it into close-fitting conformity with the pet's paw, and adjustable fastening means are provided to hold the pleated upper in place. A securing strap encircles the boot around the instep and back of the heel; a second securing strap near the rear of the boot closes its open end around the lower portion of the pet animal's leg.