The invention discloses a device for long-service life fatigue testing of guitar chords and keys. The device comprises a force application assembly, a driving mechanism, a force sensor and a control assembly, wherein the force application assembly at least is used for applying force to guitar chords and/or keys; the driving mechanism at least is used for driving the force application assembly to apply force to the guitar chords and/or keys; the force sensor at least is used for detecting force applied by the force application assembly; and the control assembly at least is used for controlling a working state of the driving mechanism according to signals fed back by the force sensor and the driving assembly. The invention further discloses a corresponding method for the long-service life fatigue testing of the guitar chords and keys. The device and method for the long-service life fatigue testing of the guitar chords and keys can be applied to press tests of pull tests of the guitar chords and key or chord grades and can well simulate actual working conditions of equivalent guitar chords and keys, and accurate testing of performances and fatigue lives of the guitar chords and keys is achieved.