Abstract: The feed property is a fundamental factor which affects the screening performance. In this research, the water and slime contents of the feed were adjusted through artificial water and slime addition. The screening performance was evaluated by screening efficiency and fines content in the oversize product. The test results showed that the increasing of water content made fine coal particles wet and bond together, thus decreasing the screening efficiency and increasing fines content in the oversize product. The increasing of slime content influenced the screening performance of fine particles, which decreased the screening efficiency slightly and increased fines content in the oversize product. High water and slime contents of the feed both had an adverse effect on the performance of dry screening.