The invention belongs to the field of polymer/nanoparticle composite materials, and relates to an infrared thermal reflection and anti-ultraviolet polyvinyl butyral (PVB) transparent film for laminated safety glass and a preparation method thereof. According to the method, nano-indium stannum oxide (ATO) is selected as functional particles, is subjected to double processing through a coupling agent and a dispersing agent and is poured into a mold to be formed and compounded after being directly and uniformly mixed with purchased or self-made polyvinyl butyral, plasticizer, antioxidant and filming agent by means of ultrasonic wave to prepare a heat-insulating PVB nano composite film. The nano-ATO particles are subjected to the double processing and the special ultrasonic dispersion process, so that the problem of agglomeration of the ATO is effectively improved; and the prepared PVB nano composite film has superior mechanical property and higher infrared reflectivity and visible light transmittance, and can be directly used for processing and producing heat-insulating, sound-insulating, anti-ultraviolet, transparent and impact-resistant multi-functional safety glass.