In recent years, the subsynchronous oscillations of power systems caused by grid-connected wind farms has occurred many times. The analysis and control method of subsynchronous oscillation stability of power grid connected with wind farms has become a scientific and engineering problem to be solved urgently. Firstly, the paper introduces the analysis methods of subsynchronous oscillation caused by grid-connected wind farms—impedance analysis method, modal analysis method and open-loop modal analysis method. And three aspects including oscillation mechanism, the accuracy of the conclusion of stability evaluation and engineering practicality are compared for three methods. Secondly, from the perspective of the negative resistance mechanism and the open-loop modal coupling mechanism, the recent study of the subsynchronous oscillation caused by grid-connected wind farms are summarized. Then, two kinds of control methods of the subsynchronous oscillation are described. Finally, the existing problems in the study of the stability analysis and control methods of the subsynchronous oscillation caused by grid-connected wind farms and the directions for future research are discussed.