The production of lightweight concrete is mainly carried out in the traditional way using lightweight ceramic aggregates. The aim of the pilot research was to verify the possibility of producing lightweight concrete based on artificial aggregate in the form of agglomerated aggregate from high temperature fly ash. A representative of such aggregate is the artificial aggregate referred to as aploporite. This aggregate is characterised by comparable grain strength to ceramic aggregates but, on the other hand, has a relatively high absorption rate of up to 30 %. Concrete formulations with up to 50% replacement of natural aggregate by aploporite have been proposed in order to achieve the volumetric weights characteristic of lightweight concrete. The results obtained confirmed that it is possible to produce lightweight concrete with this aggregate and to achieve strengths comparable to those of ordinary concrete.