A machining method for a scroll member (3, 5) of a scroll fluid machine, the scroll member including: an end plate (3a, 5a); and a spiral wall (3b, 5b) provided on the end plate, the scroll member being provided with an inclined section (3a1, 5a1, 3b1, 5b1) having a height from a tooth bottom to a tooth tip of the wall, the height being continuously changed in a spiral direction, the machining method for a scroll member comprising: a first circumferential wall surface machining step of machining one of circumferential wall surfaces of the wall in the inclined section and an adjacent tooth bottom; a second circumferential wall surface machining step of machining another circumferential wall surface of the wall in the inclined section and an adjacent tooth bottom; a tooth bottom machining step of machining only a tooth bottom between the one circumferential wall surface and the other circumferential wall surface; and a groove section machining step of forming a groove section on a tooth tip of the wall, wherein a step section (9a, 9a') is provided on a tooth bottom corner at a base of the wall, the groove section is formed on a center side in a thickness direction of the wall with respect to a position facing the step section, a machining pitch in the tooth bottom machining step is finer than a machining pitch in the first circumferential wall surface machining step and the second circumferential wall surface machining step, and characterized in that an angle of the inclined section is 0.2° or more and 4° or less. an end plate (3a, 5a); and a spiral wall (3b, 5b) provided on the end plate, the scroll member being provided with an inclined section (3a1, 5a1, 3b1, 5b1) having a height from a tooth bottom to a tooth tip of the wall, the height being continuously changed in a spiral direction, the machining method for a scroll member comprising: a first circumferential wall surface machining step of machining one of circumferential wall surfaces of the wall in the inclined section and an adjacent tooth bottom; a second circumferential wall surface machining step of machining another circumferential wall surface of the wall in the inclined section and an adjacent tooth bottom; a tooth bottom machining step of machining only a tooth bottom between the one circumferential wall surface and the other circumferential wall surface; and a groove section machining step of forming a groove section on a tooth tip of the wall, wherein a step section (9a, 9a') is provided on a tooth bottom corner at a base of the wall, the groove section is formed on a center side in a thickness direction of the wall with respect to a position facing the step section, a machining pitch in the tooth bottom machining step is finer than a machining pitch in the first circumferential wall surface machining step and the second circumferential wall surface machining step, and characterized in that an angle of the inclined section is 0.2° or more and 4° or less. a first circumferential wall surface machining step of machining one of circumferential wall surfaces of the wall in the inclined section and an adjacent tooth bottom; a second circumferential wall surface machining step of machining another circumferential wall surface of the wall in the inclined section and an adjacent tooth bottom; a tooth bottom machining step of machining only a tooth bottom between the one circumferential wall surface and the other circumferential wall surface; and a groove section machining step of forming a groove section on a tooth tip of the wall, wherein a step section (9a, 9a') is provided on a tooth bottom corner at a base of the wall, the groove section is formed on a center side in a thickness direction of the wall with respect to a position facing the step section, a machining pitch in the tooth bottom machining step is finer than a machining pitch in the first circumferential wall surface machining step and the second circumferential wall surface machining step, and characterized in that an angle of the inclined section is 0.2° or more and 4° or less.