The research of model updating based on the sine test data is less. Making full use of the accumulated sine test data plays an important role in model updating process. The vibration isolator for aerospace cabin structure is built by spring damping element. With the isolator vertical stiffness and damping as design variables, the transfer function obtained from two ends of the vibration test data as design objectives, the stiffness and damping parameters are updated by the sensitivity analysis. With the updated model, resonant frequencies agree well with test results, as well as resonant amplitudes. The model updating process is very simple and practical, which can be used in the following engineering structures.