The main goal of this course is to present basic theoretical properties of the theory of elementary particles. The first part is devoted to models of hadrons in particular chiral symmetry of strong interactions. Then next topic is the quantum chromodynamics as a gauge theory of strong interactions. Second part is devoted to the theory of electroweak interaction (Higgs mechanism, masses of gauge bosons, Higgs boson and fundamental fermions). In phenomenological applications we consider CKM matrix, neutrinos, osccillations of neutrinos, masses of neutrinos.