The first monomode microwave-assisted atom transfer radical polymerization (ATRP) is reported. The ATRP of methyl methacrylate was successfully performed with microwave heating, which was well controlled and provided almost the same results as experiments with conventional heating, demonstrating the absence of any "microwave effect" in ATRP (in contrast to several literature reports). Furthermore, we found that the main advantage of the microwave-assisted reactions over conventional reactions, i.e., a significant increase of reaction rates, only had its limited application in ATRP, even in very slow ATRP systems with high targeted molecular weights.