LNG-FPSO (Liquefied Natural Gas - Floating Production Storage and Offloading) is a promising energy-efficient method compared to onshore NG (Natural Gas) treatment facility when the gas well is located in a distant offshore ocean. The heat exchanger for LNG-FPSO should be more compact than the ones in onshore liquefaction plant due to its limited platform area. PCHE (Printed Circuit Heat Exchanger) is a newly developed heat exchanger with favorable characteristic of compactness. In this paper, we fabricated PCHE, and applied to MR-JT (Mixed Refrigerant Joule Thomson) cycle to simulate SMR (Single Mixed Refrigerant) process. Tube heat exchangers are also fabricated to compare performance of cooling system. The experimental results of the MR-JT cooling system are discussed in this paper.