New specific-heat data of YNi2B2C single crystal were measured and analyzed using two-gap model. The obtained Tc=13.77K, γn=19.74 mJ/mol K2, D=533K, ΔC/ γnTc=1.57 are consistent with those of previously reported indicating a good quality of crystal. In the superconducting state, the Ce can not be fitted to a simple isotropic-gap BCS relation. Instead, it can be well described by a two-gap model. The large gap ΔL=2.67meV and small gap ΔS=1.19meV can be obtained with 71% and 29% weighting for the density of states at Fermi surface, respectively. These results are compared with those taken by point-contact spectroscopy recently.