Since the Short Circuit (SC) characteristics of DFIG are different from traditional generators, the protection setting of DFIG becomes difficult. A practical calculation method for SC current of DFIG under symmetrical fault of power grid is proposed, considering both the characteristics of the Rotor Side Converter (RSC) and Grid Side Converter (GSC) during fault. The influence of RSC and GSC on the transient characteristics is considered under a slight voltage dip, and the influence of RSC, GSC and Crowbar protection is considered under a severe voltage dip. The SC current is regarded as the sum of the stator SC current and the GSC output current. The mathematical model of SC current calculation is established, and the delay of Crowbar action is reflected in the modeling. The calculation process is segmented by Crowbar action time. The time domain expression of SC current is obtained and the maximum and valid value of SC current is computed. The simulation analysis is achieved in PSCAD to verify the accuracy and validity of the method. This work is supported by National Key Research and Development Program of China (No. 2018YFB0904000), and Science and Technology Project of State Grid Corporation of China (No. SGJB0000TKJS1801242), and Science and Technology Project of Shenhua Group “Simulation and Fault Analysis of Double-Fed Generator Abnormal Condition” (No. SHNY (2018) 0049).