Abstract: The invention suppresses chipping of a cutting edge of a cutting tool while maintaining sharpness of the cutting edge. [Solution] A coating (20) of a replaceable knife (10) of the cutting tool is formed so that either one of a rake-face coating portion (22) that coats a rake face (14) or a clearance-face coating portion (24) that coats a clearance face (16) becomes thicker than the other. The film thickness of the thicker coating portion (22, 24) is set in a range of 0.5 ?m to 15.0 ?m, and a ratio of the film thickness of the thinner coating portion (24, 22) to the film thickness of the thicker coating portion (22, 24) is set in a range of 0.01 to 0.15.