Abstract: In this paper, fuzzy reliability methods in the corrosionpipeline are carefully studied. Determining and fuzzyreliability concepts are put forward for the first time. Three methodsare brought forward to calculate fuzzy reliability based onfracture failure criterion, FAD failure assessment diagram and residualstrength. Three additional methods are proposed to calculate determiningreliability, based on modified JC model, modified Monte-Carlomodel and modified GA-JC model.According to the observation in Shengli Oilfield certain experimental zoneswith corrosion inhibitor, temporal variation of reliability are studied.The case study shows that the method based on residual strength is betterthan the others for fuzzy reliability and modified Monte-Carlomethod is better than the others for determining reliability.