Abstract: The research on the interaction between ions and matter, based on the ions accelerator complex, play the important roles in both fundamental physics and the application aspects in many fields, such as atomic physics, material and biology researches. A novel magnetic spectrometer ion detector is developed, which is mainly composed of a high stability deflector magnet, a large-area position-sensitive detector and a space-matched scattering chamber. The new detector can accurately in-situ measure the ions’ charge state distribution and the corresponding energy spectrum. Based on the HIRFL accelerator, the calibration of the detector was completed by using the quasi-monoenergy ions and the quantitative relationship between the ion position and its energy was obtained. The optimal energy spectrum accuracy and energy resolution of the detector system are found as 0.1% and 0.8% respectively, which are shown in the calibration experiment.