A medical treatment device includes a pair of holding members configured to grasp a target part to be connected and dissected in a body tissue. At least one holding member of the pair of holding members includes an energy application portion having a treatment surface configured to contact the target part when the target part is grasped by the pair of holding members to apply energy to the target part. The treatment surface includes a high-output area configured to apply energy to the target part at a first output value for dissecting at least the target part, and a low-output area configured to apply energy to the target part at a second output value smaller than the first output value. The high-output area and the low-output area are provided continuously to each other.
