In order to provide the data support for the visual inspection test criterion of the airworthiness fireproof test of aero-engine pipeline, a method of setting temperature and strain sensors inside and outside the fire area and calculating the surface temperature and strain state of the test piece in the fire area by simulation was proposed. In order to reduce the subjectivity of visual inspection criterion in pipeline fireproof protection test, the changes of surface temperature and surface stress of the test piece in the flame area during the pipeline fireproof protection test were studied. The results show that the method can provide data support for the test results.