Abstract: Key reliability for usage of fibre glass reinforced plastics pipe lies in its chemical stability of a pipe product selected.Most encountered environments in actual application are in high temperature and pressure status.Soak test to fibre glass reinforced plastics pipes with two types of curing agents under different media environment is taken using high temperature and pressure kettle of 100 Mpa, analyzes and studies influences of media environment under high temperature and pressure on material' s moisture absorption, hardness and wet bending strength.Compares general property changes of different material before and after soaking under different testing condition and selects suitable fibre glass reinforced plastics pipes properly under different environment.