The invention discloses an insulating support for fixing a drainage wire. The insulating support is characterized in that the upper end of a metal fixed base (1) is respectively connected with one ends of two horizontal insulating support pipes (2) which are of V shapes, and the other ends of the two horizontal insulating support pipes (2) are connected with the upper end of an insulating forward-protruding tube (4); the lower end of the metal fixed base (1) is respectively connected with one ends of two inclined insulating support pipes (8) which are of V shapes, and the other ends of the two inclined insulating support pipes (8) are connected with the lower end of the insulating forward-protruding tube (4); the metal fixed base (1) is uniformly connected with two ratchet holder fixers (3), and the front end of the insulating forward-protruding tube (4) is uniformly connected with a drainage wire fixing slot (5). The insulating support provided by the invention is simple in structure, safe and reliable to use, flexible to adjust, stable to install, and wide in range of application, and the efficiency of the hot-line work can be improved and the safety of the hot-line work can be ensured.