During the launch process of space telescope, vibrations can cause irreversible harm to the main mirror. Passive vibration reduction methods are ideal for high-frequency vibrations, but they are less effective for low-frequency vibrations. To effectively suppress transmission of low-frequency vibrations, an active isolation device is introduced. The proposed method employs an active vibration isolation control strategy based on acceleration feedback. This study is carried out in three aspects, which are the design of a permanent magnet spring force actuator, anlysis of main mirror's harmonic response, and experimental verification of active vibration reduction system. Results indicate that, with the introduction of active vibration reduction system, the amplitude of low-frequency vibrations in the experimental system decreases by ~50%.