The figurative sculptures of the original chancel of the Laon cathedral (c. 1155) : remains of an axis chapel. The cathedral of Laon, provided at the end of the 12th century with a new square ended choir of ten bays, used to have, c. 1155, a choir of three straight bays, apse and deambulatory. The original straight bays are preserved and several capitals of the destroyed apse have been reused in the new choir. The old one was built in a single construction campaign and its well known architectural style differs from the rest of the cathedral. This paper intends to reesta¬ blish its figurative decoration, partly unpublished up to now. Composed of a key-stone with the image of Christ and bracket-consols with the images of the four beasts of Revelation, the decor represents a Maj estas Domini, a typical apse theme. To this group, is added a key-stone with an Agnus Dei, which must have been in the medium axe of the cathedral, above an altar. The alignment of the two key-stones closing four-part vaults allows to reconstruct the plan of an axis chapel. Besides, thanks to the homogeneity of these sculptures, we can define the style of an artist at work in other parts of the cathedral and in the neighbouring church of Nouvion-le-Vineux.