  It Is realized the theoretic - field description of Ising systems behaviour
with effect of long-range interaction in two-loop approximation in
three-dimensional space with using Pade-Borel resummation technique. The
renorm-group equations are analysed and it is chosen fixed points, defining
critical behaviour of the system. It Is shown that the influence effect of
long-range interaction can bring as to change the mode of the critical
behaviour, so and to change the type of the phase transition.
