In the present work we construct a covariant relativistic lagrangian to describe a nonzero rest mass particle, with nonzero spin, which has a special internal structure. From the minimum action principle we obtain the new relativistic equation similar to one proposed by Dirac in 1971. By this method we may study Noether’s currents, energy-impulse tensor and field moment. Interaction with other fields remains an unsolved question. Mathematics Subject Classification: 83C57, 47B15, 47B25