Abstract: In order to study the ultrafast dynamic process of highly charged state Be²⁺ ions in a strong laser, the spectral response of Be²⁺ ions was analyzed by solving the system's density matrix. It is found that the strong laser field causes a change of the electron motion in the excited state due to the transient Stark effect, corresponding to a phase change of 0.5π to the Be²⁺ system's dipole; the spectral response of Be²⁺system extends to the high and low frequencies and the line shape is changed from an isolated Lorentz line to a "wave-like" structure with the intensities of both near infrared laser pulses set to be 0.94×10¹² W/cm²; the absorption spectral line depends on the intensity of the incident laser field, pulse duration, and relative delay time, which indicates that the movement of electrons outside the nucleus in highly charged ions can be controlled by adjusting the parameters of the pump laser fields. It also find us a possible pulse-shaping scheme for soft X-rays.