To provide a gas insulation stationary induction electric apparatus of an indirect switching system which is easily transported, is intended to simplify an assembly at a site and to drastically shorten the time necessary for the completion of the assembly, and is economically excellent.

The gas insulation stationary induction electric apparatus accommodates a main transformer 10 and an in-series transformer 11 in a transformer tank 19. This main transformer 10 is constituted of a primary winding 12, a secondary winding 13 on the side of the main transformer 10, and a tap winding 14. Further, the in-series transformer 11 is constituted of a secondary winding 15 on the side of the series transformer connected in series to the primary winding 12 of the main transformer 10, and an excitation winding 16 connected to the tap winding 14 of the main transformer 10.