In this study, regional intensity-duration-frequency (IDF) curves for Turkey were developed using the available maximum rainfall intensity values for various durations (D=5, 15 and 30 minutes, and 1, 3, 6, 12 and 24 hours). Multi-nonlinear regression analysis was carried out by using nine kinds of IDF formulas, which were taken by using various IDF formulae in the literature and newly generated formulae. In order to test the reliability of the functions, two criteria were used: the determination coefficient and the mean relative error. IDF analysis in the Eastern Black Sea Basin of Turkey, which is the rainiest basin, is also emphasized and studied in detail. It has been concluded that the reliability of the results is high enough and that this paper will motivate and open new horizons to detailed studies on IDF analysis.