Abstract: The recycle treatment of carbon fiber/phenolic composites is investigated. Using the supercritical water as the action agent,when the temperature was 400 ℃, the concentration of NaOH was 1 mol/L, the reaction time was 30 min, and the filling rate was 0.62, the rate of decomposition reached 75 %.The gas chromatography and mass spectrometry analysis of the decomposition product indicate that they are the substance containing the benzene structure where the content of phenol and methyl phenol is 33 %. The rate of decomposition increases with the increase of action temperature and time. The SEM analysis of the decomposed sample shows that the surface of fiber is smooth, which indicates the considerable decomposition effect.