  We investigate transport properties of the junctions in which the graphene
nanoribbon with the zigzag shaped edges consisting of the $N$ legs is
sandwiched by the two normal metals by means of recursive Green's function
method. The conductance and the transmission probabilities are found to have
the remarkable properties depending on the parity of $N$. The singular
behaviors close to E=0 with $E$ being the Fermi energy are demonstrated. The
channel filtering is shown to occur in the case with $N=$ even.
