  We carried out a feasibility study on the measurement of the branching ratio
of H -> cc_bar at a future e+e- linear collider. We used the topological vertex
reconstructing algorithm for accumulating secondary vertex information and the
neural network for optimizing c quark selection. With an assumption of a light
Higgs mass of 120 GeV/c^2, we estimated the statistical error of Br(H ->
cc_bar) to be 20.1% or 25.7% depending on the number of vertex detector layers
at the center-of-mass energy of 250 GeV and the intergrated luminosity of 500
fb^-1.
