Abstract: The present invention proposes an improved beam structure of a dividing screen, which comprises two stand pillars, a connecting pillar, a beam, and a reinforcing part. A flat board is disposed in the beam. A gutter is disposed on a middle portion of the flat board. Two guide grooves are formed at two sides of the gutter, respectively. An outer edge of each guide groove forms a locking board to join a lamp. A locating portion is formed between the gutter and each guide groove so that a bottom end portion of the reinforcing part can be disposed thereon. Thereby, reinforcement effect can be enhanced, and delicacy and visual effect can be increased.