Ammonium dinitramide (ADN) is a potential replacement for ammonium perchlorate (AP) in composite propellants. However, its needle-like crystal morphology, thermal instability, hygroscopicity and incompatibility with many ingredients commonly used in propellant formulation make it necessary to recrystailise it into homogeneous spherical particles (prills) before they can be used in composite propellants. The melt method of polling ADN using HTPB/DOA as the liquid medium has been optimised to produce good quality spherical ADN particles, the results of which are presented in this report. The parameters studied include stirring speed, viscosity and components of liquid medium, effect of additive, design of stirrers and reactor. The investigation of water as the possible cause of particle agglomeration was also carried out. Particles of 25-250 µm can be obtained by adjustment of the liquid medium and stirring speed.