Abstract: A wind shear profile as high as 330s^-1 at 87.4km was measured by a Chaff rocket. TIs wind shear is believed to be the largest value ever measured in the mesosphere. Spectrum of the vertical velocity fluctuations in the extremely large shear layer has spectral slopes of -3.10, -1.65 and -7.11 in the buoyancy subrange, the inertial subrange, and the viscous subrange respectively. ms observation is in good agreement with the neutral density fluctuations. While the calculated inner scale and buoyancy scale do not agree with the breakpoints in the spectrum of the vertical velocity fluctuations. ms result is not consistent with the neutral density fluctuations. The relationship between turbulence and gravity wave is studied. This result suggests that enhanced turbulence is linked well with wave field saturation.