The invention discloses a single-side circular cutting blade and a cutting tool with the same. The cutting blade comprises a blade body with an approximately-circular peripheral contour. The blade body comprises an upper surface, a lower surface and side surfaces connected between the upper surface and the lower surface. A through hole for being matched with a locking screw is formed in the thickness direction of the blade body. The side surfaces are inclined and are gradually inclined inwards from top to bottom. The lower surface is a flat surface. The upper surface is inclined and is gradually inclined downwards from outside to inside. The upper surface and the side surfaces intersect to form a cutting edge. At least one locking groove which is indented inwards and used for being matchedwith a cutter body is formed in the bottom end of each side surface of the blade body. The lower section of a concave surface of each locking groove is a flat surface, and the upper section of the concave surface of each locking groove is a curved surface. On one hand, it can be avoided that the cutting blade rotates under the effect of too large cutting force, and on the other hand, the turningphenomenon of the cutting blade in the cutting process can be prevented.