Abstract: A device for varying the section of the throat of a turbine nozzle, the nozzle being formed by a plurality of stationary vanes extending radially between outer and inner annular platforms and spaced apart from one another in order to define a throat presenting a minimum flow section. The device comprises an annular element having a coefficient of expansion that is less than that of the platforms of the nozzle, the annular element being secured to the outer platform and being capable of taking up two positions: one position corresponding to no expansion of the platforms, in which the element provides continuity for the profile of the flow passage; and another position corresponding to the platforms having expanded, in which position the element projects into the flow passage so as to reduce its section.