In the study, the statistical fittings of wind speed distribution for isolated islands has been carried out. Ten years wind speed data has been collected from Bangladesh meteorological department. The data has been shorted in sequence of appropriate frequency like hourly, daily, monthly and annually mean wind speed. Two important parameters like Weibull shape factor “k” and Weibull scale factor “c” have been calculated by three methods such as Graphical method, Empirical method and Energy method. Accordingly, wind power density, availability factor and electrical energy output from the ideal turbine were assessed by using the Weibull parameters. From the analysis of the data the characteristics of wind pattern and potential of wind energy of the island has been carried out. Theoretical available power and practically extractable power by wind (watt/m2) have also been calculated. The proposed methodology can be used in any windy site to easily identify the potentiality of wind power.