The high temperature superconductor (HTS) tape is generally working in the environment of liquid nitrogen under high pressure, liquid nitrogen maySpermeated into the interior of the tape resulting from the high pressure. The material would be damaged by the vaporized liquid nitrogen, when the HTS tape recovers from low temperature to room temperature. The HTS tapes with different manufacturing technologies are soaked in high pressure liquid nitrogen and rewarmed, the changes of properties and protective measures are studied in this paper.