Astrophysical reactions proceeding through compound states represent one of the crucial part of nuclear astrophysics. However, due to the presence of the Coulomb barrier, it is often very difficult or even impossible to obtain the astrophysical S (E) factor from measurements in the laboratory at astrophysically relevant energies. The Trojan Horse method (THM) provides a unique tool to obtain the information about resonant astrophysical reactions at astrophysically relevant energies. Here the theory and application of the THM for the resonant reactions is addressed.