PURPOSE: To obtain a mechanically rigid gas insulated current transformer by providing an insulating spacer for supporting a primary coil from above and an insulating member for supporting it from below.

CONSTITUTION: A primary coil 1 and a secondary coil 2 are contained in a tank 3 sealed with insulating gas, and the coil 2 is provided so as to interlink the coil 1. The coil 1 is secured to an insulating spacer 14 provided at the top of the tank 3. An insulating post spacer 11 of an insulating member is provided at the bottom of the coil 1 on a ground side structure 12, and supports the coil 1 from below. In this case, the spacer 11 is set to a sufficient length not to be subjected to creeping breakdown between a charger and a ground. The structure 12 is held by a stripelike frame 13 in the tank 3. Therefore, since the coil 1 is supported from above and below, the coil 1 is rigidly secured, thereby obtaining a gas-insulated current transformer having high reliability.