Provided are a device (10) and a method for measuring the crispness of a food product. An item to be measured (22) comprising a porous food product is broken apart by causing the blade of a knife (14) to penetrate into the item. A vibration detector (18) attached to the knife (14) detects crack vibrations from cracks that form when the item to be measured (22) is broken apart. In a computer (20), the small crack vibrations of a predetermined vibration power or less that are included in the crack vibrations within an individual cracking duration time are extracted from the detected crack vibrations. Crispness is measured on the basis of the number of extracted small crack vibrations counted (number of cracks).