The results of studies and development of composite materials with specified properties based on amino resins and their modification products are considered. The fields of aminoplast applications and as well as methods of estimating aminoplasts' technological properties are analysed. Emphasis is put on rheological methods of evaluating the technological characteristics of aminoplasts. This is based mainly on the various modifications of rotational and capillary instruments, as well as applying chemical and physical methods for the estimation of the technological properties. Generalization are made on the basis of the authors' work on evaluating the technological characteristics of aminoplasts in non-steady state of their processing with varying temperature and time. New methods for evaluating rheological properties of aminoplasts based on the analysis of elastic-deformation grinding when aminoplasts are setting are discussed. Various methods of aminoplasts processing including pressing, injection moulding and extrusion, as well as performance characteristics of compositions based on amino resins are given.