Experimental work was carried out to obtain information concerned with the optimum conditions for the melting of frost on a heat exchanger. An ice particles layer representing frost was melted on a heated base with fins consisting of copper plates. The size ratio of the length between the fins to the height of a fin L/H ranged from 0.33 to 1.33. It was demonstrated that the heat flux supplied to melt the ice particles layer produces a large heat loss compared with the melting of the ice plate. This behavior is mainly attributable to the fact that the ice particles layer is a porous media. The ratio of the net heat flux for the melting to the supplied heat flux Qm/Qt is dependent on the density of ice particles layer, the supplied heat flux, the environmental temperature (initial temperature of the ice particle layer) and the size ratio of the fin.