Planck Absolute Entropy of the Kerr Black Hole

The thermal character of the inner horizon ofthe Kerr black hole is studied. There is a quantumthermal effect, Hawking absorption, nearthe inner horizon. We give a new formulation of the Bekenstein-Smarr formula and redefine theentropy of the black hole. The redefined entropy must goto zero as the temperature of the black hole approachesabsolute zero. The entropy satisfies the Nernst theorem, so it can be regarded as the Planckabsolute entropy of the Kerr black hole.