The objective of the paper was to determine the effect of wet agglomeration performed through mixing in a fluidized bed on some selected physical properties of agglomerates produced; an example of a model food powders was used to exemplify this efefct. The agglomeration process was performed using two methods: in a pneumatic and in a mechanically generated fluidized bed. The analysis of physical properties included: size of particles, granulometric composition, loose and tapped bulk density, porosity, flowability, and wettability. The model food powders were mixtures composed of such food powders as: whey, soy protein isolate, whey protein isolate, glucose, milk powder, and vegetable fat. Nonagglomerated mixtures were fine-grained and sparingly water-soluble powders showing a high loose and tapped bulk density, and a poor flowability. The wet agglomeration process, if carried out by mixing the model food powders, and if performed both in the pneumatically and the mechanically generated fluidized bed, makes it possible to produce a final product containing less dust, showing good flowability, and quickly dissolving in liquids. The higher bulk and apparent density rates, as well as the lower porosity of the bed with powders agglomerated by mechanical mixing show the occurrence of a closer packed structure of those agglomerates. If, during the agglomeration, wetting by carbohydrate is applied, in particular in the case of the pneumatic mixing and wetting by maltodextrin, then, it is possible to produce an agglomerate of a higher bulk density and a lower porosity compared to the agglomerate produced using water. The raw materials composition of model food powders is a factor deciding on whether or not model food powders are provided with instant wettability feature.