Using thermoplastic polymers as substrate material is an attractive approach to develop low-cost, disposable microfluidic devices. This study investigates asimple and rapid polymer replication method of fabricating microchannels by a hot roller embossing process. The hot roller embosser used in this study was modified from acommercially available film laminator, and the roller micromold was fabricated by spin coating an SU-8 layer on a flexible copper sheet. A straight microchannel measuring 5 cm long, 200 lm wide, and 41.4 lm deep was used to evaluate the imprinting performance on cyclic olefin copolymer and polyvinylchloride film. This study also investigates the effects of hot roller embossing temperature, rolling speed, and embossing pressure on the microchannel depth and geometry transfer efficiency.