The invention relates to a method for operating a gas turbine (10) below the nominal power thereof, comprising the following steps: determining a lower power threshold value (P1@TATK=const. ) of the gas turbine (10) as the power threshold value from which additional lowering of the output gas turbine power causes the gas turbine to leave a CO-emission-compliant partial load range of the gas turbine (10); providing a specified threshold value (p2) for an output gas turbine power, wherein the specified threshold value (p2) is less than the nominal power of the gas turbine; and operating the gas turbine (10) at an output gas turbine power above the specified threshold value (p2) at a constant exhaust gas temperature, wherein the inlet guide blades (13) of a compressor (12) of the gas turbine are closed further in order to reduce the output gas turbine power. In order to avoid larger temperature gradients in the preparation of an especially low partial load operation of the gas turbine (10), a sufficiently large valve is selected for the specified threshold value (p2) that the increases of the primary zone temperature, the combustion temperature, and the exhaust temperature extend over a CO-emission-compliant partial load range of the gas turbine (10) that is as large as possible.