The invention provides a quickly installed rotary spacer. Wire clamps of the spacer can be automatically buckled when being clamped; a rotary drum of a rotary inner wire camp can rotate in a transverse perforating hole of an outer wire clamp; two ends of the rotary drum are provided with inner clamping shoulders at the outer sides of outer walls on two sides of the outer wire clamp; and a buckle part is arranged at the inner side of each inner clamping shoulder. By the quickly installed rotary spacer, the installation difficulty of the rotary spacer is greatly reduced; the installation efficiency is improved by over 5 times; the structure is reliable; and the installation failure rate is greatly reduced.