The invention describes an improved process for the preparation of malononitrile by using a porous particulate solid substance as efficient absorbent. Cyanoacetamide is reacted with POCl3 as a dehydrating agent in a suitable solvent in the presence of an organic N-donor base as catalyst and a porous particulate solid substance as efficient absorbent. The product is then distilled under vacuum from the crude in the presence of a stabilizer into a receiver containing the same stabilizer, to obtain malononitrile of high purity and shelf-life.