We proposed size-dependent microparticle filtration and particle trap by centrifugal force and mechanical restriction in a microfluidic chip. Novelties of this paper are summarized as follows. (1) Filtration is robust against pressure fluctuation in microchannels, (2) Clogging of microparticles is avoided by rotation of threedimensional magnetically driven microtool (3D-MMT), (3) Size-classified microparticles can be trapped in microchannels by flow control. Microparticles having different sizes flow in circular microchannels and filtered according to their sizes by gaps between sidewalls and substrate by centrifugal force. Rotation of 3D-MMT by external magnetic force generates swirling flow in microchamber. Size-classified microparticles can be trapped in microchannel by flow control. We demonstrated filtration and trap of microparticles in a chip.