Low energy hydrogen plasma was applied to a graphite target by the linear steady plasma facility MAP(Materials And Plasma). The Hα (656.285 nm) spectrum emitted from reflected hydrogen atoms were measured to investigate hydrogen release processes from a graphite target. Broadening, peak shift and intensity of the Hα spectrum were compared with those in the previous experiments of tungsten target. The results indicated that a large fraction of hydrogen particles is released as molecules from the graphite surface.