With the booming of management method of turnkey contracting in construction area，the contractor忆s focus has
turned from construction management into multi-management of engineering, procurement，construction and testing，facing
the increasing management difficulty and risk. Therefore setting clear objectives and plans，identifying implementing risks and
making insuring measures at the beginning of the implementation of contract can make sure the project develop toward the
established goals effectively. This article narrate the role of preliminary planning in construction，and briefly state the thread of
making the preliminary planning in construction by taking the example of turnkey contracting in hydraulic engineering.