The invention discloses a petal carving process of soap carving. The petal carving process comprises the following steps of:1) processing the upper surface of a petal: obliquely inserting a soap from the surface of a raw material by adoption of a cutter, and carrying out cutting in an arc-shaped way, and carrying out cutter shaking during the cutting to ensure that lug bosses are formed on the cutting surface, so as to obtain an arc-shaped upper surface with the lug bosses; 2) processing the lower surface of the petal: obliquely inserting into the soap from an end point of the upper surface obtained in the step 1) by adoption of the cutter, carrying out cutter shaking type cutting in a wave-shaped way, and when the tail end of the cutting way is superposed with the other end point of the arc-shaped upper surface of the petal, taking back the cutter to ensure that the cutting surface is wave-shaped, so as to obtain a wave-shaped lower surface; and 3) removing the waste to form the petal. By adoption of the petal carving process of soap carving, the obtained petal is stable in stress structure and is not easy to entirely fall off due to the action of external force.