Flood is a natural disaster that caused the death of many people, environmental destruction and economical loses. Therefore, it is must be taken under control and prevent damage to the people and environment. Particularly, cities and villages have been often faced with floods that result from engineering and planning errors in Turkey. As a conventional approach, some certain calculations methods have been developed in order to estimate flood discharge, velocity, depth and recurrence in this regard. Some of them are widely used for the flood estimation such as; unit hydrograph, stochastic and statistical, Rational, MacMath, Kirpich, Mockus, SCS, Snyder and Degree-Day methods. Because, every method has some significant limiting conditions, each one gives different results for same place. According to recent researches, selection of the proper method is very important to reach more accurate results, but the best one is measuring. Therefore, a suitable method to meteorological, hydrologic, topographic conditions of a basin should be selected for the successful application. In this paper, some common conventional methods were discussed and evaluated for the aim of performing better results.