Abstract: The present invention relates to a plastic chip for PCR, having polymer valves, and more particularly to a plastic chip for PCR, having polymer valves, which can perform the temperature cycling of a small amount (nanoliter) of a sample in a microchamber at a constant temperature sensitively to temperature gradient. The inventive plastic PCR chip can perform a PCR even with a small amount of a sample through a reduction in the size of a PCR chamber included in the chip, compared to the prior PCR chip. Also, as the surface area of the PCR chamber is increased, the time taken for heating and cooling can be decreased, thus reducing reaction time. In addition, the inventive plastic PCR chip is mounted with one or more PCR chambers, so that it can amplify various genes at the same time.