Abstract: A filing tool for filing trowel edges includes a metal file and a body to contain and hold the file in a securely clamped arrangement. The body forms a relatively narrow guide slot which is given generally parallel side walls as well as a generally open bottom, front and back. The file's filing surface forms the upper boundary of the slot. The slot is given a gap that allows close fitting passage of blade of a trowel. The filing tool is used for dulling and straightening the sharp and worn edges that appear on the blade of a finishing trowel and are caused by use of the trowel while spreading, shaping and/or leveling abrasive viscous material such as cement, mortar, or grout and the like.