Process for aseptically forming containers (100) starting from parisons made of thermoplastic material, comprising the steps of: injecting sterile compressed air inside a parison arranged in a stretch-blowing forming mould (2) so as to obtain a container (100); evacuating the exhaust compressed air from the formed container (100); making at least a part of the exhaust compressed air evacuated from the formed container (100) passing through a sterile filter (SF) so as to obtain recovery sterile air; injecting the recovery sterile air in another parison arranged in another forming mould (2).