In the Present Research, We Exploited a Continuoushydrological Simulation to Investigate on Key Variables Responsible of Floodpeak Formation. With This Purpose, Adistributed Hydrological Model (Dream) Is Used In Cascade With a Rainfallgenerator (Irp-Iterated Random Pulse) to Sim- Ulate a Large Number of Extremeevents Providing Insight into the Main Controls of Flood Generation Mechanisms.Investi- Gated Variables Are Those Used In Theoretically Derived Prob- Abilitydistribution of Floods Based on the Concept of Partial Contributing Area (E.G.Iacobellis and Fiorentino, 2000). the Continuous Simulation Model Is Used Toinvestigate on the Hy- Drological Losses Occurring During Extreme Events, Thevari- Ability of the Source Area Contributing to the Flood Peak and Itslag-Time. Results Suggest Interestingsimplification For the Theoretical Probability Distribution of Floods Accordingto the Different Climatic and Geomorfologic Environments. the Study Is Appliedto Two Basins Located In Southern Italy With Different Climaticcharacteristics.