Abstract: A caisson for marine works particularly intended for use in vertical dikes which is formed by a plurality of segments (1) meant for being joined co-laterally therebetween by joining means to form a ground slab, wherein the segments (1) comprise an internal sector (2), lateral sectors (3) and an external sector (4), where said external sector (4) incorporates coupling elements; and by a series of voussoirs (5) meant for being disposed co-laterally therebetween and on the ground slab to form a surface of revolution, having an upper side (6), lateral sides (7) with interlocking means for interlocking the voussoirs (5) therebetween and a lower side (8) meant for being inserted in the segment (1) coupling elements. All of the caisson's elements are manufactured from fibre-reinforced polymer materials.