This paper shows the first results of development of the 2 millimeter-wave vector network analyzer (VNA) based on active high-order IMPATT multipliers the new type of harmonic generators. The multipliers of this type can translate the spectra of highly stable centimeter-wave oscillators to any part of the millimeter range with the output power of 20 13 dBm without additional amplification. Against Schottky-diode multipliers that are used in conventional VNAs, the active IMPATT multipliers generate more output power at large harmonic numbers that allows to lock the multipliers at their output frequencies. The phase noise of IMPATT multipliers is proportional to N against N2 in the Schottky-diode multipliers (where N is the harmonic number). We have investigated the scheme of the VNA in which the PLL and receiving mixers operated at the fundamental frequency of the heterodyne.