A fan with concealed 360-degree oscillating mechanism includes a main housing; a pivot member vertically, pivotally and turnably mounted in the housing; a first driving motor having a forward first rotary shaft and horizontally, pivotally and turnably mounted in the pivot member; an oscillating mechanism assembled between the first driving motor and a rear end face of the main housing, and having a first end driving an opposing second end to rotate eccentrically; and a set of blades fixedly connected to the first rotary shaft to locate in front of the main housing. With the first driving motor pivotally connected to the pivot member and eccentrically connected to the oscillating mechanism, the set of blades can be oscillated 360 degrees while being rotated by the first driving motor; and parts inside the main housing undertake force evenly to enable stable operation of the fan and reduced stress fatigue of the oscillating mechanism.