The plate girder is widely used in the construction of offshore steel structures and LNG modules due to its good mechanical property and structural characteristics. The constitution of plate girder is relatively simple and the pre-fabrication process is relatively regular. But it presents a high demand on process control that great attention needs to be paid to the specific details. Also all the steps are in a tight connection. The construction is involved in various drawings and welding process. Meanwhile,the inspector should not only grasp the use of inspection standards and instruments but need to be capable to record and feedback the observation during the construction. Introduces the fabrication procedure of plate girder in detail and discusses the process control measures and inspection key points during fabrication.