We use the seed bubble concept for manipulating the evaporative heat transfer in a heated microchannel with smooth surfaces. Using this concept, separation of bubble nucleation and growth is obtained to simplify the heat transfer system. Not only is the temperature excursion at the boiling incipience eliminated, but also the heat transfer system displays well-ordered and repeated flow characteristics. The heat transfer rates and wall temperatures can be controlled through adjusting the seed bubble frequency. The method provides a thermal management solution for microsystems and a tool for the study of the intricate flow and heat transfer.