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To study the influence of complex terrain with different scales on the structure of near-surface turbulence, the turbulence observational data from Semi-Arid Climate and Environment Observatory of Lanzhou University (SACOL) were analyzed. SACOL is located in typical Loess Plateau topography. The terrain around the site varies greatly with the direction. Representative data from the Northeast, Southeast, Southwest, and Northwest were selected to study the structure characteristics of the near surface turbulence. The complex topography within the flux footprint enhances the vertical scale of turbulence <i>σ_w</i> and thereby increases the vertical–longitudinal ratio of turbulence <i>A_r</i>. While the turbulent horizontal scale <i>σ_u</i> is also significantly affected by the distant terrain beyond the flux footprint. The upwind terrain undulation increases <i>σ_u</i> and reduces <i>A_r</i>. Affected by the complex terrain, the ratio of the spectrum of the vertical velocity to that of the longitudinal velocity, <i>S_w</i>(<i>n</i>)/<i>S_u</i>(<i>n</i>), is far less than 4/3 in the southwest direction, and the turbulence is significantly anisotropic.