To provide a synthetic process for urea from ammonia and carbon dioxide accompanied by formulation of an intermediate, ammonium carbamate.

(a) Ammonia is allowed to reacts with carbon dioxide to form the first liquid mixture containing urea, ammonium carbamate, water and ammonia, (b) the mixture is transferred to the decomposition and stripping step, (c) additionally heated to decompose at least a part of the mixture into ammonia and carbon dioxide, simultaneously subjecting the liquid mixture to stripping to form the second liquid mixture, (d) a part of the first gaseous mixture is transferred to the condensing step to form the third liquid mixture containing ammonium carbamate, water and ammonia, (e) the rest part of the third liquid mixture and the rest part of the first gaseous mixture are transferred to the reaction step (a), (f) the urea contained in the second liquid mixture is recovered in the following decomposition, condensation and separation steps to obtain basically pure urea and the unconverted ammonia and carbon dioxide are recycled to the synthesis step.