More and more doubly-fed induction generators（DFIGs）are used in the ever important wind energy.The inter-turn short circuit fault in the rotor will cause great harm to the generator and the wind power system.This paper derives the stator current harmonics both in healthy status and during the rotor inter-turn short circuit fault，and compares the difference between them.At the same time，the work considers the affect of winding structure.On that basis，a mathematical model based on multi-loop theory is established，and used to calculate the current of stator and rotor both in normal and faulty conditions.At last，the harmonic content of the stator current in one branch，line to line and that in the circulation of one phase parallel branch are analysed.These harmonics components can be used for detection and diagnosis of rotor winding inter-turn short circuit fault criterion.