The thermal loading of thin metal foils used as extraction windows in high current electron accelerators is one of the most important processes which should be analysed during the design of such devices. Heat loads at metal surface are also of special interest in many other plasma applications. The distribution of heat loads at the surface of thin metal foil is evaluated from the energy absorption in the foil and forced cooling with air flow. Time dependence of temperature distribution at the foil surface is calculated from the two-dimensional heat conduction equation. The simplified heat transient analysis is also given to determine the influence of scanning frequencies, electron beam size and shape ,shape of current impulses in scanning coils, energy loss in foil, the beam current and air cooling coefficient on time evolution of temperature for an arbitrary fixed point at the foil in first period of electron beam scanning. In most d.c. high current electron accelerators the concentrated electron beam generated at the cathode is accelerated along multi-gap structure and after that is dispersed over the surface of thin metal window (usually titanium (1)) by two sets of perpendicular scanning coils to obtain as uniform distribution of thermal load as possible (2). Thin metal foil (usually 50 µm thick) separates vacuum region of the accelerator from the atmosphere and is supported by a rigid frame usually cooled by water flow . The energy of the electron beam is absorbed in the foil and causes serious heating of the material, so thin foil is cooled from atmosphere side by transverse forced air stream delivered from manifolds located alongside the foil (3). The amount of the energy absorbed in window material from electron beam with given energy and current is fundamental information for design of reliable extraction system. The modification of the energy spectrum and angular distribution of primary electron beam is the result of electron interaction with the matter. In case when scattering foil is 'thin' i.e. small compared to the incident electron range, the multiple Coulomb scattering is observed together with other processes of less importance. The Monte Carlo SHOWME code was used to calculate the absorption, transmission and reflection of 800 keV electrons falling on 50 µm flat titanium foil perpendicular to its surface. The following results were obtained from the analysis (4): TE =0 .95 ± 0.01 (the energy transmission coefficient) RE =0 .005 ± 0.001 (the energy reflection coefficient) φA =0 .042 ± 0.004 (the energy absorption coefficient)