The aim of the maintenance allocation is to allocate the maintenance time to the subsystems reasonably and accurately. Traditional mean time to repair (MTTR) allocation methods are widely used in the industry. However, there are many deficiencies in practical application, which is inconsistent with the purpose of the maintenance allocation. To allocate the MTTR more precisely and reasonably, a better model is needed. The aim of this paper is to develop a maintenance allocation model, which can improve the applicability and operability, and solve the residue problem that exists in maintenance allocation. A case study is used to demonstrate how the model can be applied in practice. Copyright © 2013 John Wiley & Sons, Ltd.