We investigated the wind waves generatde on currents in a large wind-wave channel. The measurement of waves was made at 6 fetch distances up to 27.75 m by using resistance-type wave gauges for seven current speeds Uw of+29.9 to -20.3cm/sec in 50 cm water depth and for two wind speeds Ua=5.6 and 8.2 m/sec. By using the wave speed solution for the measured current profiles including the drift current true frequency spectra (equivalent to the wave-number spectra) were evaluated from the measured apparent spectra.
　The obtained true spectra show that the powers of the developing wave components increase nearly exponentially with the fetch and that water currents seem to have the effect changing the substantial fetch length. The growth rate of each wave component was obtained.
　H1/3 evaluated from η2 and the wavelengths Lm of the dominant wave were also examined,and both of them were found to change systematically, being small for the favorable current. Finally the data of H1/3 and fom were plotted in a nondimensional form by using the fetch distance F' dynamically equivalent to the fetch for no current and the reults were satisfactory despite the different current conditions for Ua=8.2 m/sec.