Summary: A new principle is proposed for constructing a nonlinear theory of coupled dynamical processes of electroelasticity. The theory is based on the equations of the two-continuum mechanics of dielectrics as a mixture of positive and negative charges in pairs, which form neutral molecules or elementary cells. The existence of an elastic potential and the linear-quadratic dependence of partial stresses on the difference of displacements of charges is accepted. Based on the definitions of a polarization vector and an associated electric field, the equations of the two-continuum mechanics are transformed into equations of electroelasticity, which describe the piezoelectric and electrostriction effects.