In order to improve the price competitiveness of the fuel cell, studies have been conducted to fabricate a catalyst layer with low Ptloading and high performance. As the catalyst layer of low Ptloading is operatedin a high current density, the mass transport capability of the catalyst layer becomes a very important factor for improving the performance. This studyproposesa multi-scale porous catalyst layer using a highinternal phaseemulsion template methodto improve the mass transport of the catalyst layer. Conventionally, many studies have been made to improve the porosity in the catalyst layer in order to improve the mass transport of the catalyst layer. However, it has been difficult to apply it to the industry due to the complex manufacturing process and the limitation ofoperating conditions as the catalyst layer composition was changed. This emulsion template method is a method which can be made in single step by maintaining the constituent components and microscopic structure of theconventional catalyst layer. The proposed catalyst layer showed a high performance improvement over the conventional catalyst layer under various conditions, and it has been confirmed through electrochemical analysis that multi-scale pore formation in the catalyst layer enhance the gas transport and mitigate the water flooding.