A series of narrow-band images of Saturn was acquired using an Acousto-optic Imaging Spectrometer (AImS) over a large number of wavelengths between 500 and 950 nm to perform a detailed study of Saturn's vertical cloud structure. The Air Force Research Laboratory's 3.67-meter Advanced Electro-Optical System (AEOS) telescope at the Maui Space Surveillance Complex (MSSC) was used for our observations on 6-11 February 2002. We photometrically calibrated the images with standard star data to obtain two sets of image cubes of Saturn. The high spectral resolution (∆λ = 1.5 -5 nm) and wide spectral coverage of AImS (500 -1000 nm) enabled us to sample different altitudes of the Saturnian equatorial region with higher vertical resolution than that achievable using conventional narrow-band filters, and to derive the wavelength dependence of aerosol optical properties. The theoretical center-limb profiles generated from radiative transfer computations were fit to the observed center-limb profiles in the Saturnian equatorial region (−10• latitude). Adopting four different cloud structure models with three different aerosol scattering phase functions, we varied up to nine free parameters and tried a total of 6000 initial conditions for optimization to seek the best solution in the vast multi-dimensional parameter space. Based on the results of the simultaneous fits to five different profiles around the 890-nm methane band and four profiles around the 727-nm methane band, we conclude that : 1) a cloud model having higher aerosol number density in the lower troposphere (0.15 -1.5 bar) is favorable, 2) the tropospheric cloud extends into the stratosphere (above 100 mb level), 3) the wavelength dependence of the upper tropospheric cloud optical thickness indicates a lower limit of the average aerosol size of roughly 0.7 -0.8 µm, 4) the average aerosol size of the vertically extended upper tropospheric cloud increases with depth from about 0.15 µm in the stratosphere to between 0.7-0.8 and 1.5 µm in the troposphere, 5) the aerosol properties in February 2002 are similar to those seen during the 1990 equatorial disturbance, suggesting a long-term mixing in the upper atmosphere of Saturn possibly associated with seasonal change.