A thermal insulation fixed support of a heat supply network pipeline comprises the heat supply network pipeline formed by a steel steam pipe coated with an insulating layer. An upper steel pipe support next to the pipe wall is arranged on the lower portion of the steel steam pipe. An upper connecting flange is welded to the lower end of the upper steel pipe support. A lower connecting flange is welded to the upper end of a lower steel pipe support. The lower end of the lower steel pipe support is fixed to a concrete chapiter. A thermal insulation plate is clamped between the upper connecting flange and the lower connecting flange, and the upper connecting flange and the lower connecting flange are fixedly connected through bolts. The upper steel pipe support and the lower steel pipe support are made of same-diameter round pipes, an arc groove with the shape the same as that of the arc wall face of the lower portion of the steam pipe is formed in the upper end of the upper steel pipe support, and the upper steel pipe support is embedded into the arc wall face of the lower portion of the steam pipe through the arc groove. The thermal insulation fixed support has the beneficial effects that the structure is simple; using and mounting are convenient; the thermal insulation effect is obvious; the thermal insulation performance of the steam pipe can be effectively improved; and the service life of the steam pipe can be prolonged.