A ceiling fan with an oscillating mechanism includes a clutch member for adjusting the angle of oscillation according to a user's need. When the motor is actuated, the rotating torque induced by the motor and the transmission mechanism is less than the rotational resistance of the clutch member such that the motor may drive the fan to oscillate. Further, when the user applies an external rotational force greater than the rotational resistance of the clutch member, the user can swing the fan to any angle as desired without rotating or shifting other members except the fan and the fan suspension tube. In this manner, undesired damage of the mechanism or motor due to inappropriately applied external force can be avoided efficiently.