A slip control device for an electric vehicle which is a vehicle including an electric motor configured to rotationally drive a drive wheel, the slip control device performing slip control of the electric vehicle, the slip control device comprising: a drive wheel rotation number observation section configured to observe the number of rotations of the drive wheel; a driven wheel rotation number observation section configured to observe the number of rotations of a driven wheel via a rotation speed sensor of a rotation detection section that has a response cycle time Ts that in a predetermined low-speed range varies according to vehicle speed; a slip control section configured to perform, in a control repetition cycle time Tc, a series of slip control which determine whether or not a slip state has occurred, on the basis of the number of rotations of the drive wheel observed by the drive wheel rotation number observation section and the number of rotations of the driven wheel observed by the driven wheel rotation number observation section, and which decrease a torque command value to the motor if the slip state has occurred; a vehicle speed detection section configured to detect a vehicle speed; and a control repetition cycle change section configured to make the control repetition cycle time Tc of the slip control section variable and then lengthen the control repetition cycle time Tc of the slip control section so as to substantially coincide with the response cycle time Ts of the rotation detection section, when the vehicle speed detected by the vehicle speed detection section is in the predetermined low-speed range, wherein the slip control section includes: a slip watch range determination section configured to determine whether or not the number of rotations of the drive wheel has exceeded a watch range number of rotations which is set so as to be lower than the drive wheel maximum number of rotations, if the slip state determination section determines that the number of rotations of the drive wheel has not exceeded the drive wheel maximum number of rotations; and a watch range-time torque reduction section configured to decrease the torque command value to the motor if the slip watch range determination section determines that the number of rotations of the drive wheel has exceeded the watch range number of rotations. a drive wheel rotation number observation section configured to observe the number of rotations of the drive wheel; a driven wheel rotation number observation section configured to observe the number of rotations of a driven wheel via a rotation speed sensor of a rotation detection section that has a response cycle time Ts that in a predetermined low-speed range varies according to vehicle speed; a slip control section configured to perform, in a control repetition cycle time Tc, a series of slip control which determine whether or not a slip state has occurred, on the basis of the number of rotations of the drive wheel observed by the drive wheel rotation number observation section and the number of rotations of the driven wheel observed by the driven wheel rotation number observation section, and which decrease a torque command value to the motor if the slip state has occurred; a vehicle speed detection section configured to detect a vehicle speed; and a control repetition cycle change section configured to make the control repetition cycle time Tc of the slip control section variable and then lengthen the control repetition cycle time Tc of the slip control section so as to substantially coincide with the response cycle time Ts of the rotation detection section, when the vehicle speed detected by the vehicle speed detection section is in the predetermined low-speed range, wherein the slip control section includes: a slip watch range determination section configured to determine whether or not the number of rotations of the drive wheel has exceeded a watch range number of rotations which is set so as to be lower than the drive wheel maximum number of rotations, if the slip state determination section determines that the number of rotations of the drive wheel has not exceeded the drive wheel maximum number of rotations; and a watch range-time torque reduction section configured to decrease the torque command value to the motor if the slip watch range determination section determines that the number of rotations of the drive wheel has exceeded the watch range number of rotations. a slip watch range determination section configured to determine whether or not the number of rotations of the drive wheel has exceeded a watch range number of rotations which is set so as to be lower than the drive wheel maximum number of rotations, if the slip state determination section determines that the number of rotations of the drive wheel has not exceeded the drive wheel maximum number of rotations; and a watch range-time torque reduction section configured to decrease the torque command value to the motor if the slip watch range determination section determines that the number of rotations of the drive wheel has exceeded the watch range number of rotations.