PURPOSE: To prolong the life of a knife for vegetables by connecting a blade with an operable and curved blade to a grip in a rockable state and forming the grip as a nearly semicircular sheath with two side surface guides.

CONSTITUTION: Synthetic resin parts 1 and 10 of the same shape, which are used as the side surface guides and form the grip 2 together, are inseparably connected with each other with an adhesive on a connecting web and an insertion bushes 8 to form a case (sheath) with respect to the blade 20. The bushes 8 are connected to each other respectively by reinforcing ribs 9. The blade 20 is detachably held by a bearing bush at the grip 2 and provided with a head part 21 with neck parts 22, and the parts 22 are shifted to a circular sector 23 forming an angle α. The angle is spread at least to 2×α at a length being nearly a half of the blade 20 and this spread part 24 if formed like a ring sector. The blade 20 is desirably punched from a stainless steel plate and provided with a ground edge 25.