  After Y(4630) is discovered, theorists have given various explanations. We
find that if Y(4630) is interpreted as the D-wave resonant state of $\Lambda_c
\bar {\Lambda}_c$ system, the particle mass, decay width and all quantum
numbers are consistent with experimental observations. We use the Bonn
approximation to get the interaction potential of one boson exchange model,
then extend the complex scaling method (CSM) to calculate the bound and
resonant states. The results indicate that the $\Lambda_c \bar{\Lambda}_c$
system can form not only the bound state of S wave, but also the resonant state
of the high angular momentum, and the $^3D_1$ wave resonant state can explain
the structure of Y(4630) very well.
