Ultrafine YW2A and traditional YW2 cemented carbide cutters were prepared by vacuum sintering, 06Cr19Ni10 stainless steel was turning under variable cutting speeds. OM, dynamometer（YDC-Ⅲ89B）, portable roughness tester (TR100) and SEM (S-3400N) were used for examination of metallographics, cutting forces, surface roughnesses and tool wears respectively. Compared with YW2, YW2A has higher hardness and traverse strength, lower cutting force and better surface quality, smaller oxidation wear, but both tools show spalling wear mainly.