Embodiments of the present invention relate to an RRU device and an assembly thereof. The RRU device includes: an enclosure, where the enclosure includes a front-end plate and a back-end plate that are respectively set on two lengthwise ends of the enclosure, multiple parallel spaced heat sinks are set on two widthwise sides of the enclosure and between the front-end plate and the back-end plate, and the front-end plate and the back-end plate extend along a widthwise direction of the enclosure by a length which is greater than a length by which the heat sinks extend; and a joint part set on the enclosure, where the joint part is used to fasten two side-by-side radio remote unit devices together.