Résumé : Elastic and inelastic alpha scatterings on C10 were measured using a 68-MeV/u radioactive C10 beam incident on the recently developed MAIKo active target system. The phenomenological effective α-N interaction and the point-nucleon density distribution in the ground state were determined from the elastic scattering data. The cross sections of the inelastic alpha scattering were calculated using this interaction and density distribution and were compared with the experiment to determine the neutron quadrupole transition matrix element Mn between the ground state and the 21+ state at Ex=3.35 MeV in C10. The deduced neutron transition matrix element is Mn=6.9±0.7(fit)±1.2(sys)fm2. The ratio of the neutron transition strength to proton transition strength was determined as Mn/Mp=1.05±0.11(fit)±0.17(sys), which indicates that the quadrupole transition between the ground state and the 21+ state in C10 is less neutron dominant compared to that in C16.