This study has assessed the fabric of the fishing vessel-oriented marine life jacket in accordance with the basic methods and procedures of the uncertainty measurement evaluation. With the each group (10 pieces each) of longitudinal and latitudinal fishing vessel-oriented marine lifejacket cloth – polyester fiber Oxford cloth – as the object of study, it has set up the mathematical model to analyze and evaluate the sources of uncertainty of the tensile and rupture strength, compound uncertainty, and expanded uncertainty. It aimed to find the biggest uncertainty component – uncertainty resulting from the errors in human reading, clearly analyze the key points for control during the inspection process of the tensile and rupture strength for marine lifejacket cloth, and control the uncertainty factors which affect the measurement results, so as to ensure the measurement accuracy and fully reflect the reliability and accuracy of the inspection results by the laboratory. Meanwhile, it urgesd the inspectors to enhance their technical skills. This study provides technical support for boosting the inspection level of the fishing vessel-oriented marine lifejacket cloth. ［Chinese Fishery Quality and Standards, 2014, 4(5):55-60］