An articulating head of a power tool is disclosed in the present invention, which includes a base member adapted to couple to a main body of the power tool, an articulating member pivotably connected to the base member, and a locking device coupled to the articulating member for locking an orientation of the articulating member with respect to the base member. The base member contains a first power transmission part which is capable of receiving mechanical driving power from the main body of the power tool. The articulating member contains a second power transmission part mechanically coupled to the first power transmission part. The locking device has an actuation lever rotatable about a pivot axis between a free position and a lock position.