Aulnois-sous-Laon (French pronunciation: [o(l)nwa su lɑ̃], literally Aulnois under Laon) is a commune in the department of Aisne in the Hauts-de-France region of northern France.

The D967 road also passes through the commune from Crecy-sur-Serre in the north continuing to Laon in the south.

[3] The Ru d'Alnois rises south of the village and flows northeast changing to the Ruisseau de Longuedeau and forming the northeastern border of the commune before continuing northeast joining the Ru des Barentons which eventually joins the Souche river at Barenton-sur-Serre.

[3] [3] Blazon: Or, with escutcheon gules charged with three martlets in sable supporting a castle of four towers argent port and windows sable all supported by two Alder branches fructed in vert and posed in inverted chevron, all accompanied by three martlets sable at dexter chief, sinister chief, and base.

List of Successive Mayors of Aulnois-sous-Laon[4] Two sites in the commune are registered as historical monuments: