The Libra Extend Well Test (EWT) project is composed of 2 satellite wells interconnected to an FPSO with an external Turret anchor. One well is the producer, with 6-inch service lines and 8-inch production line in lazy wave risers configuration. The other well is the injector, with two 6-inch gas flow lines also in lazy wave compliant configuration. In the project planning several ac-tions were considered in order to guarantee the first oil date determined by the project, while the production unit (FPSO) was not available in the location and ready to pull-in campaign. One of these actions studied and later adopted was the pre-laying operation of the flexible lines with floaters in the lazy wave configuration of the production line of the production well. Later on, simi-lar studies were done considering the pre-laying of injection lines also. As this type of operation is not a track records at Petrobras for the ultra-deep water scenario, additional studies were nec-essary to ensure its feasibility and the safety execution. The objective of this article is to present the previous studies and the result achieved in the pre-laying operation of flexible line with float-ers in the lazy wave configuration of the Libra EWT service line.