The utility model relates to a prevent bird device of nesting for dangling tower, which comprises a housin, the space between cross yoke plate, left side composite insulator grading and shielding ring and the right side composite insulator grading and shielding ring of the pressure shield ring that lies in the top in the tower that dangles, below is located to the casing, the casing surface is the arc surface, and bilateral symmetry, the base of casing is equipped with the last border checkpoint of recess, cross yoke plate go into in the recess, the casing about both sides pass through bolt and locknut respectively with left side composite insulator grading and shielding ring and right side composite insulator grading and shielding ring fixed connection. The utility model discloses the shell surface is slick and sly, does not have edge or acute angle to exist, increases the degree of difficulty that birds were nested to avoided birds to drop on on the shaft tower or when circling in the air near the shaft tower, its excrement influences insulating and leading to the flashover between conductor and the shaft tower. In addition, shell surface slyness has been avoided arousing electric magnetic field intensity's sudden change under the condition in forceful electric power magnetic field.