This paper presents several micropumps which generate pumping power through the chemical production of gas. Decomposition of hydrogen peroxide by aid of catalyst results in the production of oxygen. Hydrogen peroxide is separated by paraffin from catalyst before reaction. The decomposition of hydrogen peroxide by catalyst is initiated through melting the paraffin by an underlaid microheater. An initial triggering of the micropump by input of electric current is sufficient for the continuous actuation through the decomposition reaction. The operation of oxygen micropump can be tightly controlled if hydrogen peroxide is decomposed only by heating with microheater. For the production of carbon dioxide, sodium bicarbonate in a chamber is decomposed by heating. Alternatively, water droplet is caged by paraffin layer and released by heating. The released water dissolves citric acid powder and then, sodium bicarbonate reacts with citric acid and carbon dioxide is produced.