A positron tomography device using a micropattern detector is provided. The positron tomography device comprises: a micropattern gas detection device accelerating electrons so as to generate second ionized electrons; a lead-out strip through which an electrical signal is transmitted by the second ionized electrons; and a signal processing unit for processing the electrical signal detected in the lead-out strip arranged at a predetermined position, wherein a plurality of micropattern gas detection devices is disposed in a ring shape, and the lead-out strip is disposed outside the micropattern gas detection device.