To provide a work assisting device useful at the time of performing work by a hedge trimmer composed of an arm provided with an arm placing base for mounting the elbow or the like of a worker or the like capable of reducing the fatigue of the worker, performing continuous work and improving work safety.

This device is composed of a base member 1 held by a body part belt 16 wound around the body part of the worker and the arm 4 whose one end is attached to the base member 1 and other end is provided with the arm placing base 5 for mounting the elbow or the arm of the worker held so as to be able to change an attaching angle to the base member 1. Also, it is preferable to form an extension expansible part 13 whose length is expansible, contracted and adjusted in the middle of the arm 4.