The moisture content of fine fuels is one of the key indicators for assessing the danger of forest fires. In addition, many models for determining the risk of fire in the forest environment are based on the prediction of moisture content in fine fuel, i.e. moisture content limiting value. The main goal of the PhD. thesis was to determine the limiting value of forest litter moisture, at which it will be ignited. This was done in laboratory conditions, where the effect of moisture content change of oak and pine litter on its flammability in the presence of different wind speeds was tested. Three initiation sources were used to initiate the combustion, namely a smouldering cigarette butt, a lighter flame and a burning oak and pine cube. The moisture content of the litter, the speed of the wind and their interaction significantly affected the capability to initiate and propagate the fire. The moisture content limiting value for oak litter, at which fire was initiated and subsequently propagated into the surroundings, was set to 11%. The moisture content limiting value for pine litter, at which the fire was initiated and subsequently propagated into the surroundings, was found to be 26% for a lighter flame and a burning cube. The moisture content at which it was not possible to ignite the fuel with the lighter flame for 30 s was set to 30%. Similar value we found by a burning wooden cube used as the initiation source. In order to evaluate the impact of changes in meteorological condition, wind conditions, topographic conditions, physical (especially fuel moisture) and fire parameters of forest fuel, modelling of fire behaviour was performed in the FARSITE program. The results of the modelling pointed to the interaction of factors that influence the fire behaviour. We included a number of factors there: air temperature, relative air humidity, wind speed, total precipitations, and topographic conditions. These all affect the behaviour of the fire and the overall extent of the burned area, fire site respectively.