In order to systemize the analysis method of fatigue crack initiation origin (fatigue failure maximum weak part), fatigue failure maximum weak part and the relationship to material texture were analyzed. Pearlitic steel smooth material was used for the material made into the example. First, a mechanical engineer's focus and technology were used, specification of a fatigue failure maximum weak part in pearlitic steel smooth material was performed, and relation between material texture and a fatigue failure maximum weak part was clarified. Then, analysis to material texture was carried out using the knowledge and analysis technology of crystallography of a metallurgist. A fatigue test and analysis showed that a flat face existed at the fatigue crack initiation origin of pearlitic steel smooth material. In addition, as a result of the analysis of a flat face, the formation mechanism of fatigue crack initiation origin (flat face) was able to be clarified, and systematization of analysis was able to be attained.