The present invention relates to a protector to protect trees in apartment houses which is applicable to various trees as the protector can be installed regardless of the diameter and circular cross-sectional shape of a tree. The tree protector according to the present invention comprises: a tree restraint unit (100) comprising of multiple plates (110) connected in a line to be rotated through pins (P) while having a circular arc shape as a whole, tightly-contacting plates (120) extended downward with the same curvatures as those of the inner circumferential surfaces of the plates (110) to contact tightly with the circumferential surface of a tree (1), hooks (130) formed at the outer circumferential surfaces of the plates (110), and reinforcing bars (140) installed at the bottoms of the plates (110) and the back sides of the tightly-contacting plates (120) so as to provide connection and support, so that the plates (110) on opposite sides are interconnected through fixing means (F) to surround and restrain the tree (1) a support unit (200) comprising of a support rod (210) whose one end is installed to be rotated on the reinforcing bar (140) of the tree restraint unit (100) and which supports the tree restraint unit (100), and a stand (220) firmly fixed to the ground (2) and installed to be rotated on the opposite end of the support rod (210) and an anchor unit (300) securing the stand (220) on the ground. In accordance with the embodiment, the tree protector is applicable to various trees as the protector can be installed regardless of the diameter and circular cross-sectional shape of a tree planted in an apartment house, due to inter-rotational structures of circular arc-shaped plates in the tree restraint unit and even when the ground in an apartment house is inclined, the tree protector can be installed easily and simply regardless of installation place since the installation angles of the support rod and the stand can be adjusted to the inclination of the grou