  We theoretically investigate the tunneling conductance of the $d+ip$-wave
superconductor which is recently proposed to be realised at the (110) surface
of a high-$T_c$ cuprate superconductor. Utilizing the quasiclassical
Eilenberger theory, we obtain the self-consistent pair potentials and the
differential conductance of the normal-metal/$d+ip$-wave superconductor
junction. We demonstrate that the zero-bias peak of a $d$-wave superconductor
is robust against the spin-triplet $p$-wave surface subdominant order even
though it is fragile against the spin-singlet $s$-wave one. Comparing our
numerical results and the experimental results, we conclude the spin-triplet
$p$-wave surface subdominant order is feasible.
