The principle and condition of the polymerase chain reaction (PCR) has been analyzed, and instrument system of gene amplification which takes M30627FJPGP as the core was excogitated. The design proposal of the hardware was provided, the factors which influence the calefaction and refrigeration effect of PCR appearance as well asthe special requirements to electromagnetic compatibility were analyzed, and the controls algorithms of fuzzy self-adjustment PID that to bedefinite to systematic characteristic was proposed. Experiment shows that, the temperature-controlledprecision of the systematic can be achieved to ?0.1degrees Centigrade, the velocity of temperatureheating up and cooling is fast, the repetitiveness isfine, and instrument prototype of a machine has been used in temperature controlling of gene increasing already. The design method of the systematic software and hardware also has certain interrelated significances to other similar high-accuracy temperature control occasions.