A sectional rack includes at least four vertical supports, at least two shelves, and a plurality of clamping members. Each vertical support includes two laterally juxtaposed left and right posts, and a plurality of connecting members connected to between the two posts. Each clamping member defines a vertically extended receiving recess, which has two wing portions formed at two ends of an open side thereof, and is sized for one post of the vertical support to partially set therein, allowing the clamping member to assemble to the vertical support. The shelves are respectively provided at four corners with an outward-opened C-shaped clamping member each for tightly fitting around and thereby pushing the two wing portions of the clamping member toward each other to firmly clamp the post in the receiving recess, so that the four corners of the shelves are firmly connected to the posts of the four vertical supports.