We investigated structure deformation dynamics of acetylene molecules in charge-changing collisions of 6 MeV O4+ ions by means of a momentum 3D imaging technique. We obtained an angular correlation between fragment ions of H+ and C+ produced in (H+ + C+ + C2+ + H), (H+ + C+ + C+ + H) and (H+ + C+ + CH+) measured for single electron loss and capture collisions. It was found that in fragmentation channel of (H+ + C+ + CH+) bending motion Of C2H2 occurs strongly compared with (H+ + C+ + C2+ + H) and (H+ + C+ + C+ + H). We concluded that the structure deformation is caused by electronic and vibrational excitation.