A cutting machine comprising: a cutting portion comprising: a motor; a motor housing (50; 150) accommodating the motor; an output shaft configured to be rotated upon rotation of the motor, a cutting blade being configured to be detachably attached to the output shaft; a battery pack serving as a power source of the motor; and a battery pack attaching portion disposed in the motor housing and including a pair of rail portions (51B, 52B) with which the battery pack is engageable; a base having a contact surface suitable for a workpiece to be placed thereon; and a swing support mechanism connected to the base and the cutting portion and including a swing shaft extending in parallel to the output shaft, the swing support mechanism supporting the cutting portion such that the cutting portion is swingable about the swing shaft between a top dead center and a bottom dead center in a direction parallel to a side surface of the cutting blade; wherein each of the motor and the battery pack attaching portion is positioned in a direction perpendicular to output shaft, characterized in that the motor housing (50; 150) is constituted by at least two split pieces (51, 52) each having a mating surface (51A, 52A), the at least two split pieces (51, 52; 151, 152) contacting with each other at the mating surfaces (51A, 52A), the pair of rail portions (51B, 52B) having one rail (51B, 52B) and another rail (51B, 52B) those individually positioned at different ones of the at least two split pieces (51, 52; 151, 152), and in that the battery pack attaching portion and the motor are disposed radially outward of the cutting blade. a motor; a motor housing (50; 150) accommodating the motor; an output shaft configured to be rotated upon rotation of the motor, a cutting blade being configured to be detachably attached to the output shaft; a battery pack serving as a power source of the motor; and a battery pack attaching portion disposed in the motor housing and including a pair of rail portions (51B, 52B) with which the battery pack is engageable; a base having a contact surface suitable for a workpiece to be placed thereon; and a swing support mechanism connected to the base and the cutting portion and including a swing shaft extending in parallel to the output shaft, the swing support mechanism supporting the cutting portion such that the cutting portion is swingable about the swing shaft between a top dead center and a bottom dead center in a direction parallel to a side surface of the cutting blade; wherein each of the motor and the battery pack attaching portion is positioned in a direction perpendicular to output shaft, characterized in that the motor housing (50; 150) is constituted by at least two split pieces (51, 52) each having a mating surface (51A, 52A), the at least two split pieces (51, 52; 151, 152) contacting with each other at the mating surfaces (51A, 52A), the pair of rail portions (51B, 52B) having one rail (51B, 52B) and another rail (51B, 52B) those individually positioned at different ones of the at least two split pieces (51, 52; 151, 152), and in that the battery pack attaching portion and the motor are disposed radially outward of the cutting blade.