A portable air cleaning apparatus includes a housing, an actuating and sensing device and an air cleaning unit. The housing includes an inlet through hole and an outlet through hole. The actuating and sensing module and the air cleaning unit are disposed inside the housing. The actuating and sensing module includes an actuating device and a sensor. The actuating device drives an external air to flow into an interior of the housing via the inlet through hole and discharge the air via the outlet through hole, so as to form an internal air flow. The sensor detects the internal air flow to generate an air-sensing result, such that the actuating and sensing module can accordingly control the air cleaning unit to turn on, turn off, or adjust cleaning intensity. Thus, the portable air cleaning apparatus can monitor and automatically clean the ambient air at the same time.