  This paper concerns the low Mach number limit of weak solutions to the
compressible Navier-Stokes equations for isentropic fluids in a bounded domain
with a Navier-slip boundary condition. In \cite{DGLM99}, it has been proved
that if the velocity is imposed the homogeneous Dirichlet boundary condition,
as the Mach number goes to 0, the velocity of the compressible flow converges
strongly in $L^2$ under the geometrical assumption (H) on the domain. We
justify the same strong convergence when the slip length in the Navier
condition is the reciprocal of the square root of the Mach number.
