Karimata Strait Throughflow (KSTF) and Makassar Strait Throughflow (MSTF) are parts of Indonesian Throughflow (ITF), which is an ocean bridge to connect the Pacific and Indian Oceans. The interactions between the two ocean basins can occur via the ITF. Here we investigate how the KSTF and MSTF individually affect the Indo-Pacific oceanic climate in an oceanic general circulation model (OGCM). Four 100-yr experiments with climatological forcing have been conducted. Two of them are to open or close ITF completely like previous work, but the other two runs only open a part of ITF.