Abstract: Voltage source converter-based high voltage direct current transmission (VSC-HVDC) has been widely used in large-scale renewable energy transmission and cross- regional transmission due to its economic and stability advantages. However, in recent years, several high-frequency resonance (HFR) events have occurred in modular multilevel converter-based HVDC systems at home and abroad. These events seriously threaten the safe and stable operation of power systems and restrict the large-scale consumption of renewable energy. In order to deeply study and solve this new stability problem of power system, this paper first summarizes some typical high-frequency resonance events that have occurred at home and abroad. Then, the research statuses of HFR in terms of impedance modeling, stability analysis and mitigation strategy are summarized. Finally, the difficulties and challenges faced in the current research are pointed out and the future research directions are prospected.