An auxiliary member for a bird nest comprises a rectangle-frame-shaped first layer and a rectangle-frame-shaped second layer which are welded by galvanizing angle irons respectively. The first layer and the second lay are arranged in parallel and four columns are connected between the two layers to support the two layers. The frameworks of the first and the second layers are provided with bird nest areas and blank areas. The bird nest areas and the blank areas in the first layer and in the second layer are arranged crosswise. That is to say, the bird nest areas of the second layer are arranged over the blank areas of the first layer, and the blank areas of the second layer are arranged over the bird nest areas of the first layer. Edges of the first layer are provided with interconnecting pieces used for fixed connection with a crossbeam of an iron tower. When the auxiliary member is installed in the middle of the iron tower, birds are attracted to build bird nests on the auxiliary member, so that the case that the birds build bird nests on the top of the iron tower is avoided.