A “non-local” measurement scheme was introduced in order to clarify spin injection into multi-layer graphene at room temperature (RT) with reliability. The introduction of the “non-local” method can exclude spurious signals, such as anisotropic magnetoresistance effect, from the measurements, because an electric current pass is completely separated by a spin current pass (spin current is flow of pure spin) and an electrochemical potential of spin current is detected as proof of spin injection. Spin injection and spin current generation in MLG was succeeded at RT, which was the first success of observing spin current in molecules. Furthermore, a “local” magnetoresistance effect was recently observed at RT, and spin coherence was precisely and quantitatively estimated by using a Hanle-type spin precession method, where spin coherent length and spin coherent time were estimated to be 1.6 μm and 120 ps at RT, respectively.