The impact of inertia control of doubly-fed induction generator（DFIG）wind turbines on the small-signal stability of systems is studied.Firstly，the principle of DFIG wind turbines offering inertia responses is discussed，followed by the introduction of two approaches of inertia control.Then，possible influences of two control schemes on system small-signal stability are analyzed.Finally，on the basis of simulation，the modal analysis method is adopted to analyze the influence characteristics of different control strategies and various control parameters on system small-signal stability.Analysis results show that inertia control may have an appreciable impact on the system small-signal stability.Therefore，security constraints of small-signal stability should be carefully considered when designing the control strategy and parameters.