A street tree guard ensuring easy assembly work and having secure coupling strength is provided. The street tree guard includes an inner supporting member which is configured to be installed on a ground around a street tree, an outer supporting member which is configured to be disposed while being spaced apart from the inner supporting member outward, a covering member which configured to be disposed between the inner supporting member and the outer supporting member. Each of the inner supporting member and the outer supporting member includes a plurality of base members configured to be disposed at equal intervals and a plurality of connecting members configured to connect two facing ends of the base members to each other. If a part of the street tree guard is damage, only the damaged part is replaced for maintenance, thereby reducing the maintenance sot. The street tree guard ensures easy installation. The street tree guard ensures simple assembly work, thereby making it easy to clean a surrounding of the street tree.
