The invention provides a test piece configuration method for an overrun fracture test of an aero-engine rotor. The test piece configuration method comprises the following steps of: S1, carrying out overrun analysis on a rotor assembly of an aero-engine, S2, determining a minimum fracture margin wheel disc in the rotor assembly, S3, constructing a preliminary design scheme of the test piece configuration, S4, performing overrun fracture analysis on the configuration of the test piece, S5, judging whether the test piece configuration design meets criterion requirements or not, S6, determining the configuration of the test piece, S7, finishing processing and assembling of the test piece, and S8, determining the fracture rotating speed of the rotor part. The method is based on an extreme strain method, does not contain any coefficient and factor, is simple and direct in test verification, and can save a large amount of test expenditure and time. Therefore, the fracture starting position ofthe rotor can be predicted accurately, the worst combination within the position tolerance range can be directly selected as the worst size of the fracture, the operability is high, a theoretical basis is provided, and the method is suitable for being applied to the engineering development process.