This dissertation focused mainly on theoretical study of formic acid (HCOOH) decomposition on the Ni(111), Pd(111), Ni(211), Pd(211), Pt(211) and Mo2C(101) surfaces, since formic acid has been considered as one of potential materials in hydrogen storage and generation. The formate route plays the dominating role in formic acid decomposition; and the rate-determining step is the dissociation of formate into surface CO2 and H. In addition, the Ni(111) surface was also employed to investigate the mechanism of full acrolein hydrogenation.