Carrying out a semi-classical Ehrenfest dynamics simulation based on the time-dependent density functional theory, we investigate the light-harvesting property of a π-conjugated dendrimer, star-shaped stilbenoid phthalocyanine (SSS1Pc) with oligo (p-phenylenevinylene) peripheries and show that an electron and a hole transfer from the periphery to the core through a π-conjugated network when an electron is selectively excited in the periphery. The one-way electron and hole transfer occurs more easily in dendrimers with a planar structure than in those with steric hindrance because π-conjugation is well maintained in the planar structure. The present results explain recent experiments.