A novel oxygen micropump is described in this paper. Pumping power is generated through the chemical production of oxygen gas. Decomposition of hydrogen peroxide by aid of catalyst results in the production of oxygen. Hydrogen peroxide is separated by oily paraffin from catalyst before the start of decomposition reaction. The decomposition of hydrogen peroxide by catalyst is commenced 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. Liquid sample in reservoir is pushed by the produced oxygen gas and flows through a microchannel. Commercially available thin paraffin layers can replace paraffin for easier fabrication. Moreover, the operation of oxygen micropump can be tightly controlled if hydrogen peroxide is decomposed only by heating. Oxygen micropump will be a preferable component of lab-on-a-chips (LOCs) as well as the source of pure oxygen for chemical systems. (C) 2003 Elsevier B.V. All rights reserved.