An outdoor dry transformer having a shield made of a high functional fiber. The transformer includes a transformer body having a core and first and second coils wound on the core; a shield surrounding the transformer body, the shield comprising a high functional fiber material which is capable of blocking moisture penetration from outside and has breathability; and a transformer housing having at least one vent in side and bottom faces thereof, the transformer housing configured to house the transformer body and the shield therein. The transformer does not use the insulating oil, thereby preventing any fire induced from the insulating oil. It is also possible to prevent environmental pollution caused by polychlorinated biphenyl as well as save resources.