In the Aircraft redelivery process, MRO companies often experience delays in the completion of aircraft maintenance and repair before being handed over to the lessor (aircraft owner). A study was conducted to analyse the risk causes with a systematic risk management approach. The risk assessment study refers to ISO 31000, which consists of 4 stages: risk-cause identification, risk-cause classification, risk analysis, and evaluation, and risk treatment identification. Root-cause and Pareto analysis also used to help to strengthen the analysis and decision making. This study was conducted in one of the MRO Companies in Indonesia. From a study of 7 cases of aircraft redelivery delay in 2001-2017, it was found that the dominant cause of the risk was late in decision making on new findings of aircraft condition, bad data management, bad system planning, availability of materials and workers, and poor quality of maintenance work. After the risk assessment process, it was obtained that 6 risks causes need to be reduced, 3 risks need to be shared/transferred, and 3 risks need to be accepted.