A continuous process for the synthesis of urea from liquid ammonia and liquid carbon dioxide has been developed and described. A small unit for the production of 175 pounds of urea per day has been designed,constructed, and successfully operated. An exothermic autoclave reaction is indicated both by calculation and observation. Thirty-five to thirty-seven per cent conversions of the reactants to urea have been attained in a reaction period of less than 2 hours.