PROCESS FOR MANUFACTURING A BICYCLE SADDLE, which provides a central through channel and which has: - a hull with a through hole at the central through channel of the saddle; - a polyurethane layer as a padding element; - a liner adapted to cover the polyurethane layer, said process providing for the following steps: - arranging the liner on the hollow surface of a mould; - creating a vacuum between the liner and said hollow surface to allow a perfect adhesion between the aforesaid ones; - pouring polyurethane into said hollow surface, previously covered by the liner; - positioning the hull on the surface of a counter mould; - mutual approaching and closing of the mould and counter mould and consequent positioning of the counter mould at the hollow surface of the mould; - expansion of the polyurethane, which completely fills the space between the liner and the hull; - mutual moving away of mould and counter mould; - extraction of the set of hull, polyurethane and liner of the mould, wherein said liner is subjected to a previous processing step so as to present a cap-like structure at the region in which the channel of the saddle will be present once formed and in that the step of arranging the liner presenting the cap-like structure on the mould takes place taking care to arrange said cap-like structure on a projection, specifically provided in said mould, adapted to engage with a concavity specifically provided for in said counter-mould; said process being characterized in that, at the end of all the previous steps, the portion of the cap-like structure which covered the projection and which protrudes above the edges of the hole of the hull is mechanically removed and in that the liner is made by the following steps: - creating a hole on a semi-finished liner, at the region where the channel of the saddle will be present, once formed; - welding of a cap-like structure to the semi-finished liner at the hole, so that the open edges of the cap-like structure coincide substantially with the edges of the aforesaid hole. - a hull with a through hole at the central through channel of the saddle; - a polyurethane layer as a padding element; - a liner adapted to cover the polyurethane layer, - arranging the liner on the hollow surface of a mould; - creating a vacuum between the liner and said hollow surface to allow a perfect adhesion between the aforesaid ones; - pouring polyurethane into said hollow surface, previously covered by the liner; - positioning the hull on the surface of a counter mould; - mutual approaching and closing of the mould and counter mould and consequent positioning of the counter mould at the hollow surface of the mould; - expansion of the polyurethane, which completely fills the space between the liner and the hull; - mutual moving away of mould and counter mould; - extraction of the set of hull, polyurethane and liner of the mould, wherein said liner is subjected to a previous processing step so as to present a cap-like structure at the region in which the channel of the saddle will be present once formed and in that the step of arranging the liner presenting the cap-like structure on the mould takes place taking care to arrange said cap-like structure on a projection, specifically provided in said mould, adapted to engage with a concavity specifically provided for in said counter-mould; - creating a hole on a semi-finished liner, at the region where the channel of the saddle will be present, once formed; - welding of a cap-like structure to the semi-finished liner at the hole, so that the open edges of the cap-like structure coincide substantially with the edges of the aforesaid hole.