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The first ever experimental results over Indian Thar Desert region concerning to height integrated aerosols size distribution function in particles size ranging between 0.09 to 2 mu m such as, aerosols columnar size distribution (CSD), effective radius (R-eff), integrated content of total aerosols (N-t), columnar content of accumulation and coarse size aerosols particles concentration (N-a) (size < 0.5 mu m) and (N-c) (size between 0.5 to 2 mu m) have been described specifically during winter (a stable weather condition and intense anthropogenic pollution activity period) and pre monsoon (intense dust storms of natural mineral aerosols as well as unstable atmospheric weather condition period) at Jaisalmer (26.90 degrees N, 69.90 degrees E, 220 m above surface level (asl)) located in central Thar desert vicinity of western Indian site. The CSD and various derived other aerosols size parameters are retrieved from their average spectral characteristics of Aerosol Optical Thickness (AOT) from-UV to Infrared wavelength spectrum measured from Multi-Wavelength solar Radiometer (MWR).The natures of CSD are, in general, bio-modal character, instead of uniformly distributed character and power law distributions. The observed primary peaks m CSD plots are seen around about 10(13) m(2) mu m(-1) at radius range 0.09-0.20 mu m during both the seasons. But, in winter months, secondary peaks of relatively lower CSD values of 10(10) to 10(11) m(2)/mu m(-1) occur within a lower radius size range 0.4 to 0.6 mu m. In contrast to this, while in dust dominated and hot season, the dominated secondary maxima of the higher CSD of about 10(12) m(2)mu m(-3) is found of bigger aerosols size particles in a rage of 0.6 to 1.0 mu m which is clearly demonstrating the characteristics of higher aerosols laden of bigger size aerosols m summer months relative to their prevailed lower aerosols loading of smaller size aerosols particles (0.4 to 0.6 mu m) in cold months. Several other interesting features of changing nature of monthly spectral AOT, R-eff, N-t, N-a and N-C (particles/m(2)) have been discussed in detail in this paper.