Abstract: Provided is a portable air projection apparatus, which may be used in conjunction with a mobile phone and can project the content displayed on the screen of the mobile phone in the air. The apparatus may be carried with one and used instantly. The portable air projection apparatus comprises: a vapor projection curtain generation device, which can generate a gaseous curtain wall through a vapor outlet; a communication interface, which can be connected with a portable mobile communication device via a signal; a signal transceiving and processing unit for receiving a display signal from the portable mobile communication device through the communication interface, and converting the display signal into a projection control signal; and a projection lens for generating a projection display screen on the gaseous curtain wall according to the projection control signal.