Abstarct: To supply water in Kalardasht area, AlamKooh glacier plays an important role in recharge of the lakes in the areas especially in draught and summer periods. This fact can be more important when the mountain glacier is surrounded by farm lands and water irrigation in summer and late spring depends on the water melted from the glacier. The glacier thickness is one of important quantities that can be used for prediction of the water melted from the glacier and for investigation of glacier changes in various years. Determination of thickness of snow, debris and ice in mountainous glaciers is generally made rarely due to extremely cold climate conditions, high elevation of glaciers, risk of falling large snow segments or balls. And also, the time and personal needed in geophysical investigation for this urpose. Within past years, the method of ground penetrating radar (GPR) has been used extensively for investigation of surface and internal structures of glaciers. This geophysical method demonstrates different structures in the glaciers considering the electrical permittivity constrast between ice, air, debris, water and baxsement of the glaciers. Due to the transparency of icefor electromagnetic (EM) waves, and also, that the GPR method, which is non-destructive, fast and accurate, this method has been used in this thesis for determination of thickness and baxsement topography of AlamKooh glacier. The GPR data acquisition has been made by 25 MHZ transmitter antenna using common offset method, and transmitter and receiver spacing or separation of 6 meters on AlamKooh glacier, Kelardasht, Mazandaran. This data acquisition has been carried out by water resources center of Water Research Institute of Iran in June 2013. Nearly all of the glaciers in the weat of the study area (including Alamchal, Takht-e-chal and Takht-e-soleiman) have been surveyed by GPR method. In this thesis, considering the limitation of data accessibility only data from 6 survey lines in Alamchal glacier have been processed and interpreted using REFLEXW software, (version 7.1.6). Furthermore, in this thesis, forward modeling of GPR response for synthetic models similar to glacier including targets of snow, debris, ice and baxsement of the glaciers using tow-dimensional forward modeling algorithm of GPR data by the finite-difference method in the REFLEXW has been carried out, and the results have been presented. The results indicate a relative similarity between two-dimensional (2-D) GPR sections obtained from forward modeling of synthetic models and 2-D GPR section obtained from acquired data on the glacier in the study area. After applying various processing methods on the acquired data in the study area, the EM waves reflections from the interfaces of different laxyers have been detected, and determination of thickness and baxsement topography of the glacier, the moderate and cold zones of the ice, the type of the glacier, that is multithermal glacier and the holes on the surface of the glacier have been successfully possible. The reflections from the glacier baxsement have been detected, and by assigning of EM wave velocity in ice (0.16 m/ns), the varying thickness of 50-94 m from the data has been estimated. In this research, the electrival resistive nature of the glacier has caused high depth of penetration of GPR waves. Finally, after investigating GPR depth section, it was observed that the topography of the glacier baxsement is relative accurate copy of the topography of the glacier surface