Karst topography is a landscape shaped by the dissolution of a layer or layers of soluble bedrock, usually carbonated rock such as limestone or dolomite. Investigation and comparison of these landscapes with another landscape that have non-karstic topography for is necessary watershed managers. The main objective of this research is to compare hydrological characteristics of two types of catchments including karstic and non-karstic catchments. Mojen catchment has a karstic topography that mostly covered by limestone, and Gorgdareh as a non-karstic topography in west side of Mojen catchment where both are located in central Alborz Mountain in Semnan province, with the similar climate, area, slop and annual rainfall. Thses two catchments are compared in view of maximum discharge, runoff coefficient, specific discharge and relationship between maximum instantaneous discharge and maximum daily mean discharge. Results indicate that runoff coefficient for Mojen\\\'s karstic catchment is 1.28 and for Gorgdareh that is Non- karstic catchment is 0.35. Specific discharge for Mojen on a concurrent period is 0.0174 m3/sec/km2 when for the Gorgdareh it is 0.051m3/sec/km2. Relationship between maximum instantaneous discharge and maximum daily mean discharge for Mojen is 1.145 and for Gorgdareh is 1.380. Finally this research showed that application of rational and empirical formulas for karstic catchment is unreliable.

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