Catalyst for fuel cell, electrode for fuel cell, membrane-electrode assembly for fuel cell and fuel cell system using the same

A catalyst for a fuel cell includes an active metal catalyst and a composite supporter supporting the active metal catalyst. The composite supporter includes a spherical-shaped supporter and a fibrous supporter, wherein the fibrous supporter is included in an amount of about 5 wt% to about 40 wt% based on the total amount of the composite supporter. In addition, an electrode for a fuel cell using the same, a membrane-electrode assembly for a fuel cell including the electrode, and a fuel cell system including the membrane-electrode assembly are also disclosed.