Kendilo coal with high ash content was washed using a sink-float method to improve its quality for gasification. Samples from East Kalimantan were tested with different sizes and densities. The best washing results were achieved with a fraction of -12.5+5.6 mm at a density of 1.36 g/cc for Bindu Block's coal, reducing ash content to 8% with 50% recovery. Betitit Block's coal reached 50.82% recovery at the same fraction but with a density of 1.39 g/cc.