An improved process for the preparation of 2-pyrrolidone by the liquid phase hydrogenation of succinonitrile in the presence of a hydrogenation catalyst and ammonia, whereafter the resulting hydrogenation product is hydrolyzed with water. A hydrogenation catalyst in the form of a fixed bed is used, and a liquid phase of succinonitrile and liquid ammonia is passed over the catalyst at a temperature of between 50.degree. and 130.degree. C.