This paper discussed three schemes to obtain vibration modal frequency. First, theoretical numerical method was introduced to simulate the vibration modal by ANSYS software. Second, one kind of traditional experimental modal analytical scheme was designed to obtain modal frequency by computer random signal and vibration analysis system (CRAS). Third, a new experimental modal test scheme was proposed by FBG test platform. A completed case on modal frequency of the cantilever was carried out by three different schemes, in order to evaluate their merits and drawbacks by comparison. Accordingly, computational modal numerical method in combination with experimental modal test method can meet the analytical demand of modal parameters in practice engineering.