A method for the error correction of a vectorial network analyzer, where a primary system calibration is initially implemented using a calibration kit. Following this, a first, secondary error correction is implemented on at least two one-port networks of the vectorial network analyzer. After this first, secondary error correction of the one-port networks of the vectorial network analyzer, a second, secondary error correction is implemented, where either two one-port networks are through-connected in an ideal manner or a measurement is implemented on a reciprocal two-port network. The corrected system-error values from the first, secondary error correction are used even in this further measurement, and overall, a high-precision, calibrated multi-port network analyzer is obtained.