  We study the influence of a magnetic field $H$ on the zero-bias conductance
peak (ZBCP) due to zero-energy Andreev bound state (ZES) in normal metal /
unconventional superconductor. For p-wave junctions, ZBCP does not split into
two by $H$ even for sufficiently low transparent junctions, where ZBCP clearly
splits for d-wave. This unique property originates from the fact that for
p-wave superconductors, perpendicularly injected quasiparticle form ZES, which
contribute most dominantly on the tunneling conductance. In addition, we show
that for $p_{x}$+i$p_{y}$-wave superconductor junctions, the height of ZBCP is
sensitive to $H$ due to the formation of broken time reversal symmetry state.
We propose that tunneling spectroscopy in the presence of magnetic field,
$i.e.$, $magnetotunneling$, is an promising method to determine the pairing
symmetry of unconventional superconductors.
