Global Ionosphere Maps (GIM) from GNSS data are important for ionospheric variation study by providing the global vertical total electron content (VTEC).However,because of uneven distribution of GNSS tracking stations,especially lack of stations in ocean areas,conventional GIM have lower accuracy and reliability there.But Satellite altimetry and DORIS can compensate GNSS for data in ocean areas,therefore a more accurate and reliable GIM can be formed with integration of the three kinds of data.Accordingly,the paper builds GIM with temporal interval of two hours by integrating GNSS and space-based ionospheric data.The result shows that VTEC change -4.6 – 2.6 TECu by adding satellite altimetry and DORIS data,and that maximum RMS decreases 5 TECu and accuracies of GIM in ocean areas are improved significantly.