The newly developed open superconducting magnetic resonance imaging (MRI) system, which combines the advantages of the high magnetic fields of superconducting MRI systems and open characteristics of permanent MRI systems, has great potential in clinical and research applications. However, few pulse sequences are applicable to this system. In addition, further testing on this system is needed. Therefore, in this paper, an inversion recovery gradient echo (IR-GE) pulse sequence was developed based on the features of the 0.7 Tesla open superconducting MRI system. An MR Solutions spectrometer was used to control the IR-GE pulse sequence. The developed IR-GE pulse sequence was applied to a pure water phantom using different inversion recovery times (TI). The results of the theoretical analysis and experiments indicate that the developed IR-GE pulse sequence could be effectively applied to the 0.7 Tesla open superconducting MRI system.