A method of failure event report correlation is proposed. A UE detects a failure event in a first cell served by a first base station, and the UE is assigned with a previous C-RNTI. The failure event may include a radio link failure, a handover failure, or a RACH failure. The UE then performs an RRC establishment procedure with a second base, and the UE is assigned with a new C-RNTI. After the RRC establishment, the UE transmits a failure event report along with the correlation information to the second base station. The second base station then forwards the failure event report and the previous C-RNTI to the first base station. The first base station can correlate the failure event report with the previous failure event based on the previous C-RNTI to avoid double bookkeeping and improve MRO decision for SON.