The present invention discloses a portable fretsaw comprising a fretsaw bar connected to a shaft. Driving forces of an electric motor is transferred to the shaft through a pinion wheel, an intermediate gear and a final driving gear fixed to the mandril for rotating the fretsaw bar, the shaft is supported to the pivoting support part, a cleaver mechanism has a cleaver and a member to be supported,the cleaver is positioned at the back side of the fretsaw bar in the cutting direction, when the fretsaw strip is located to project beyond a biggest projecting amount of a base part, the member to be supported is supported in the surface area of the circumference besides the area most adjacent to the base part of a pivoting support part.