Abstract: To suite requirement of continuously development of coal preparation process and simplify test steps in laboratory,based on the comparison of data from 0-3 mm size fraction float-and-sink test with the combined data which from the 0-0.5mm size fraction float-and-sink analysis and 0.5-3mm size fraction,analyzed the feasibility of making 0-3 mm coarse coal slime float-and-sink test using centrifuge,expanded the applicable scope of particle size of coal fines in float-and-sink test method set in standard of GB/T19092 and simplified the test steps,so it can better service for production.