N-vinyl carbazole (VCZ) was grafted on cellulose acetate film using simultaneous cobalt-60-gamma ray irradiation grafting technique. Absorption, excitation, and emission spectral studies on the grafted film were carried out to ascertain the grafting of VCZ on the polymer matrix. Laser-flash photolysis studies with the solution of grafted film indicate the opening of the double bond of VCZ, which leads to the grafting. On the basis of the observed results, the mechanism of grafting in the system was proposed.