The present invention relates to a length-adjustable branch drooping and shaking prevention tree shape forming support having 360-degree rotatable support. The present invention relates to a length-adjustable type tree shape forming support which prevents a branch from being deformed and drooping as fruit of a fruit tree grows in a harvest season and has heavy weight and the fruit tree cannot endure the weight of the fruit, and in particular, prevents branches from breaking when the fruit tree shakes in rainy and windy weather. The length-adjustable branch drooping and shaking prevention tree shape forming support has an adjustment function for adjusting a length of a holder for supporting a branch to the support and a length of the support and a fastening function (a function for fastening a fixation band) of the fixation band for fastening the support to the tree. According to the present invention, a length of the support can be selectively adjusted in accordance with the distance between a branch to another branch. A branch can be tightly fixated, regardless of thickness, by the fixation band to a fastening device arranged separately from the support. The length-adjustable branch drooping and shaking prevention tree shape forming support pulls up a branch drooping downwards and holds a branch and another branch. Therefore, the length-adjustable branch drooping and shaking prevention tree shape forming support can protect tree and fruit from strong wind or heavy rain. The support can be attached and detached as needed in an easy manner. A bendable support groove is arranged to come in close contact with a branch and is installed to enable the support to come in close contact with a tree. The length-adjustable branch drooping and shaking prevention tree shape forming support protects a fruit tree and fruit with user convenience and stability resulting from tight fixation and also contributes to an increase of income of a farmer who cultivates fruit trees.COPYRIGHT