In the submarine pipeline laying project, the S-lay pipelaying system and J-lay pipelaying system are needed to complete the pipelaying task. The reasonable design of space layout of the two systems is made respectively to integrate them on the same deepwater floating crane pipelaying vessel. The collaborative operation of double pipelaying system is designed to enable the two systems to share the pipe segment prefabrication line and the Abandonment and Recovery (A&R) winch system, so as to realize the complementary advantages and improve the pipelaying operation efficiency.