Abstract: A process for synthesizing ammonia is disclosed comprising the steps of generating the synthesis gas from hydrocarbons by the primary reforming of said hydrocarbon with steam and by the secondary reforming of the resulting gaseous mixture with oxygen; subjecting a portion of the starting hydrocarbon mixed with the steam to a tertiary reforming in which the necessary heat is provided by the gaseous reaction mixture leaving the secondary reforming; causing the ammonia synthesis to occur at low pressure with drying of the gas sent to the synthesis reactor by employing a molecular sieve; causing the ammonia contained in the reacted gas to be absorbed by water; and subjecting the ammonia solution so obtained to a distillation which may be a conventional distillation step or one effected by means of two distillation columns operating at different pressures.