[Problem] To provide a fall prevention unit for an aerial work platform that does not require direct locking between a handrail of a work platform and a net, is excellent in workability when attached to the handrail of the work platform, and can also be used to prevent scattering. do. A fall prevention unit 3 which can be attached to a handrail of a workbench of an aerial work vehicle, comprises a rectangular frame 5 composed of a long side 10 and a short side 11, and a net stretched over the entire frame 5. 6, and mounting means for mounting the frame 5 on the handrail of the work platform of the aerial work vehicle. The first short side portion 14 and the second short side portion 15 are connected by a hinge portion 16, and the entire fall prevention unit 3 can be opened and closed around the hinge portion 16, Further, the frame 5 is provided with a narrow angle maintaining means for maintaining the narrow angle of the short side portion 14 . [Selection drawing] Fig. 2【課題】作業台の手すりとネットとの直接の係止が不要で、作業台の手すりへの装着作業性に優れ、さらに、飛散防止にも使用可能な高所作業車の落下防止ユニットを提供する。【解決手段】高所作業車の作業台の手すりに装着可能な落下防止ユニット3であって、長辺部10と短辺部11とから成る長方形の枠5と、枠5全体に張られるネット6と、枠5を高所作業車の作業台の手すりに装着するための装着手段と、を備え、落下防止ユニット3は、枠5の短辺部11が第1短辺部14と第2短辺部15とに分割され、第1短辺部14と第2短辺部15とがヒンジ部16によって連結され、落下防止ユニット3全体がヒンジ部16を中心として開閉可能とされており、さらに、枠5が短辺部14の挟角を維持する挟角維持手段を備える。【選択図】図2