The electric spark sensitivity of 32 polynitro arenes was determined as the spark energy, E_ES,required for 50 per cent initiation probability. A relationship between the E_ES values and the squares of detonation velocities of the polynitro arenes was established. This relationship represents a certain form of Evans-Polanyi-Semenov equation and,therefore,it signalises an identity of chemical mechanisms of the primary fragmentation processes in the molecules of polynitro compounds during their detonation and in the initiation of their decomposition and/or explosive transformation by the action of electric spark. However,the way of energy transfer from the spark to reaction centre of molecule of the said compounds is not yet clear.