The aim of this research was to assess the use of biomass ash for fertilisation of mineral soil. The study involves the analysis of the effects of biomass ash applied to soil on the changes of pH and the content of the available forms of phosphorus, potassium and magnesium as well as on total content of zinc, copper, manganese, nickel, cadmium and lead. The field experiment was conducted in 2013 in Duninowo near Ustka. In experiment grown two plants spring: Spring barley - var. Sebastian, and wheat - var. Bombona. The use of ash from biomass and Biotop compost as fertilisers did not result in any significant changes of soilpH. The use of ash from biomass and Biotop compost caused a significant increase in the contents of available phosphorus, potassium and magnesium in soil. The threshold values of the analysed trace elements in soil, as specified by the Regulation of the Minister of Environment, were not exceeded in any of the fertilising variants in the experiment.