The nonlinear interaction of two collinear ultrasonic beams in the presence of turbulence in water has been investigated. The transmitting unit was driven continuously at 3 and 5 MHz. A 1‐in, diameter water jet (20 ft/s) was located with nozzle 75 cm from the beam path which intersects the flow at 90° and originates 40 cm from it. Forward scattering angles were measured in the plane of the jet and sender by a 2‐MHz receiver located 185 cm from the interaction region. The energy spectrum of the turbulence had frequency components in the range of several Hertz to 2 kHz. In the presence of turbulence the difference frequency was broadened by sidebands up to +1 kHz from the center frequency for scattering results taken in the angular range −30° to +30°. The received spectrum was asymmetric relative to the center frequency. Comparisons are made between the spectral broadening of a primary 2‐MHz signal and the broadening associated with a difference frequency component (2 MHz) that exists due to the mechanisms of the parametric array. These results are an extension of earlier experiments of the authors on the scattering of sound by sound in the presence of turbulence for a crossed‐beam arrangement. [J. Acoust. Soc. Am.64, S14 (A) (1978)] [Work supported by the Office of Naval Research.]