By making use of the kinetic equation and the global entropy formula reported in the first paper of this series, we have derived the entropy balance equation and the accompanying molecular formulas for local entropy density, entropy flux and entropy production for real fluids at an arbitrary density. We have thereby obtained an extension to real fluids of the Boltzmannian irreversible thermodynamics which is based on the Boltzmann equation for ideal fluids. The theory presented provides us with a molecular basis for the continuum mechanics formulation of irreversible thermodynamics by Coleman, Noll, Gurtin and their coworkers: The macroscopic constitutive functionals in their theory can now be calculated from the various molecular formulas for the relevant quantities in our theory.