In the present paper the addition of some functional ingredients to common wheat flour and its effect on the quality parameters and the microstructure of the extrusion-cooked precooked pasta products was investigated. The expansion ratio, water absorption index, a cooking degree and the organoleptic assessment were tested with the standard methods for pasta products. The microstructure was characterised by SEM microscopy technique at different magnifications. The processing parameters (like, a screw rpm and a moisture content of raw materials) established some physical properties and the microstructure of the pasta products processed on a modified single screw extrusion-cooker TS-45. The addition of functional components like salt, egg powder, disodium orthophosphate, methylcellulose and ascorbic acid had a strong effect on the surface and the interior structure of products as well as dried precooked pasta quality. The best results associated with the uniform and compact structure of pasta products and excellent quality were obtained at processing a flour mixture enriched with a methylcellulose additive at 80-100 rpm and at 80-95°C temperature range.