In an exhaust gas turbocharger for an internal combustion engine comprising a
radial flow exhaust gas turbine and a compressor, which is connected to the turbine
via a shaft, the turbine having a radial inflow duct and a radial inlet flow passage,
which leads to the turbine wheel and in which a variable geometry vane structure
for changing the cross-section of the radial inlet flow passage is supported between
two support walls fixed to the turbine casing, one of the support walls projects
into the inflow duct, in such a manner that the rear side of this support wall
is spaced from the inner wall of the inflow duct wall so that the exhaust gas within
the inflow duct is in contact also with the rear side of this support wall.