Abstract: In this paper, an interpenetrating network(IPN) organic-inorganic gel system was prepared by water soluble phenol-formaldehyde resin, sodium silicate and water-resistant agent based on sol-gel technology.The gelation time of IPN gel system shortens with the concentration increase of water soluble phenol-formaldehyde resin, while gelation strength increase.When the concentration of sodium silicate is 0~3%, the gelation time lengthens and the gelation strength enhances with concentration increase.The interpenetrating network structure formed by water soluble phenolic-resin and sodium silicate is dense and symmetrical.The system can be used as a high temperature plugging agent and satisfied the deep sealing condition.