This paper present a new dynamic window function having variable or adjustable spectral characteristics. A new dynamic window function proposed in this paper is a combination of hamming, Blackman-Harris, chebwin, and Kaiser Window function. Blackman-Harris, chebwin, and Kaiser Window functions have been used to compare with the suggested proposed window function i.e. a combination of hamming, Blackman-Harris, chebwin, and Kaiser Window function. Compare observation has been done with the help of MATLAB simulation. The simulation results show that the suggested proposed window function provides better ripple-ratio, main lobe width and side lobe roll-off ratio as compared to Blackman-Harris, chebwin, and Kaiser-window function. While comparing with Blackman-Harris, chebwin, and Kaiser Window functions, proposed window function provide quite good spectral performances with a very small compromisation of one of the spectral characteristics.