This book contains a brief study on synthesis and application of noble metal graphene composites. A facile synthesis of Pt/Pd alloy nano-particles via chemical reduction method is provided and graphene nanosheets were prepared via modified hummer's method followed by preparation of their composites. Their electrochemical data toward ethanol oxidation was obtained in basic medium, giving interesting outcomes. These results indicate that the catalytic material could be a good candidate for ethanol sensing and can also be utilized as a supporting material of high-loading metal catalyst in fuel cells. The application of this catalyst for ethanol sensing was very promising with sensitivity well maintained even in the presence of various interfering agents.