The present invention discloses a method for detecting a cause for a Radio Link Failure (RLF) or handover failure is provided. The method includes when a User Equipment (UE) enters a connection mode after encountering RLF or handover failure, sending a RLF report that the UE encounters RLF or handover failure to a base station; determining, by the base station, a cause for RLF or handover failure according to the RLF report, if it is determined that the cause for RLF or handover failure is a problem of Mobility Robustness Optimization (MRO) or a problem of coverage, when it is a problem of MRO, sending, by the base station, a MRO report to a base station at which a cell which triggers handover for the last time is located.