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In this research, Empirical Orthogonal Function (EOF) method is conducted to assess the dynamics of Indian Ocean characteristics, (i.e. sea surface temperature (SST) anomaly and equatorial wind), as the response of IOD for last 30 years (1988 – 2017). Based on the EOF analysis, IOD explains about 23.1% of the total variation of interannual SST anomaly (EOF second mode). While due to the equatorial wind components, IOD explains about 40.9% of the total anomalous zonal wind variation (EOF first mode) and 21.8% of the total anomalous meridional wind variation (EOF second mode). Based on the EOF and cross correlation analysis, its obtained some accurate indices and able to describe the dynamics of Indian Ocean during IOD events, such as SSTdyn (for SST anomaly dynamics), Udyn (for zonal wind anomaly dynamics), and Vdyn (for meridional anomaly dynamics). Moreover, based on the composite analysis of these Indian Ocean dynamics indices, during the five (six) positive (negative) IOD events from 1988 to 2017, the negative (positive) SST anomaly in the eastern Indian Ocean (0°–15°S dan 90°–120°E) followed by the positive (negative) SST anomaly in the western Indian Ocean (10°N–10°S dan 40°–60°E) and the central Indian Ocean (5°S–10°S dan 70°–80°E) occur in June and reach the peak in September-October. The anomalous SST is also accompanied by anomalous wind in the region of 5°N–10°S dan 70°–100°E, which starts by the occurance of anomalous northerlies (southerlies) meridional wind in June-July, continues by the occurance of anomalous easterlies (westerlies) zonal wind in the following month, and reaches the peak in October.