The phase field method was used to study the domain structure and switching in nanocomposites consisting of ferroelectric nanorods and a dielectric matrix. The results demonstrate that the domain structure and hysteresis loop shape are controlled by the nanocomposite structure and by the misfit between the nanorods and matrix. Hysteresis loops consisting of triangular offset loops and a narrow central part with a low remnant polarization and coercive field can be obtained as well as rectangular loops with a large remnant polarization and coercive field. The possibility of the switching behaviour control through the misfit control is discussed.