A fan with concealed oscillating mechanism includes a main housing, a first driving motor, a second driving motor and a curved link gear all located inside the main housing, and a set of blades located outside the main housing and connected to a rotating shaft of the first driving motor. The first driving motor has a connecting rod rotatably received in a receiving tube provided in the main housing. The second driving motor is located behind and connected to the first driving motor, and has a rotating shaft being perpendicular to that of the first driving motor. The curved link gear is connected at an end to the second rotating shaft and at another end to the main housing, such that when the second driving motor operates, the first driving motor is brought to oscillate while the set of blades stably rotates to thereby change the direction of produced airflow.