Abstract: Plate fin heat exchanger has been widely used in medium and small sized LNG plant. However, in large scale LNG plant, the fluid uniform problems are difficult to be resolved for the plate fin heat exchanger because multiples of cold boxes are uesd and plat pin heat exchangers are connected in parallel which results in significant degradation of heat transfer performance. The fluid uniform problems are the key restriction factors of application process for plate fin heat exchanger in large scale LNG plant. In this paper, a new type of heat transfer structure is developed by means of optimization design for existing plate fin heat exchanger. The heat performance is simulated and the results reveal that the new type heat exchangers maintain good heat performance with the natural gas treated in large scale. The study results can provide a reference for the structure design in large scale LNG plant.