The present invention includes methods and apparatuses for producing hydrogen peroxide using microchannel technology. An exemplary process for producing hydrogen peroxide comprises flowing feed streams into intimate fluid communication with one another within a process microchannel to form a reactant mixture stream comprising a hydrogen source and an oxygen source such as, without limitation, hydrogen gas and oxygen gas. Thereafter, a catalyst is contacted by the reactant mixture and is operative to convert a majority of the reactant mixture to hydrogen peroxide that is withdrawn via an egressing product stream. During the hydrogen peroxide chemical reaction, exothermic energy is generated and absorbed by the fluid within the microchannel as well as the microchannel itself.