With the geothermal reinjection well and geothermal prduction well, the double well same floor reinjection test was made in Tertiary geothermal reservoir of porous type with pressure. By the development of anticorrosion filter for geothermal reinjection and the matching technology, all kinds of blocking in the process of reinjiction were solved, no matter they were caused by physical, chemical or biological factors, and further decrease of reinjection and loss of reinjection ability at early stage were avoided.