Abstract: A hand file designed expressly for sharpening the cutting edge of a chisel tooth chain saw which cutting edge has substantially diagonal and horizontal beveled components. The file comprises an elongated flattened blade portion with rounded side edges, a finger hold at one end and a tang at the other, in which the filing surface area extends around both side edges of the elongated blade portion and 1/8 of an inch into the upper and lower flattened surface, and in length from the tang to the finger hold. The remainder of the flattened surface is smooth and provided with guide lines for angling the file with respect to the linear movement of the saw. The rounded edges are semi-circular and the thickness of the file is equal to the circumference of the semi-circle, and determines the fit between the depth gauge and the opposing cutting tooth on the variously sized chains, and the maneuverability into the beveled cutting edges of the saw tooth.