We calculate the valence quark generalized parton distributions (GPDs) of the lightest pseudoscalar meson, pion, in an isospin asymmetric nuclear matter at zero temperature by employing a light-cone quark model. The medium modifications in the unpolarized GPDs have been incorporated by taking inputs from the chiral SU(3) quark mean field model. The electromagnetic form factors (EMFFs) and charge radii have been calculated for both the vacuum and in-medium cases. These results are found to be in agreement with the available experimental data and other model predictions.