tThe dynamics of the glass transition in Se76Te21Sb3chalcogenide glass was studied under non-isothermalmeasurements using differential scanning calorimetry (DSC). The experimental result of the kinetic glasstransition phenomenon, at different heating rates (5–40 K/min), was analyzed on the basis of the relax-ation process occurring in the transition temperature range. The activation energy of the glass transitionwas determined using an advanced isoconversion kinetic methods as well as from the heating ratedependence of the glass transition temperature. The fragility index m of the glass was estimated from themeasurements of the activation energy of the relaxation process, which characterizes the glass transition.Moreover, the isoconversional kinetic analysis of the experimental data show that the activation energyof glass transition process is varying with the degree of transformation (and hence with temperature)from the glassy to the super cooled phase.