Abstract: One-stage design contains basic design and detailed design, and the project review point can be cancelled, so usually it can accelerate the construction of project. In this paper, the characteristics and key points of one-stage design mode are discussed by taking a project as an example, and some suggestions are put forward for the engineering design management of large and medium-sized petrochemical projects.

Key words: one-stage design, large and medium-sized petrochemical project, design basis