This study presents a method of strength analysis of the connecting rod which is the core part of internal combustion engine. Contemporary high performance engine connecting rod must maintain high level of durability. To this end, proper stress level and fatigue-life during engine operation should be guaranteed. Using the beam theory, thick cylinder theory, compound cylinder theory, and oil hole and notch stress concentration theory, the stress analysis is carried out. In analyzing the shank part, Rankin's buckling formula is employed. And also, modified Goodmann diagram is used to predict the fatigue safety factor. If the information for sectional shape is given, sectional area, center of gravity, and 2nd area moment of inertia would be calculated automatically. This successive analysis procedure is coded by the Fortran language
By using a commercial finite element analysis program, the same model is analyzed by applying an equivalent boundary condition. The deformed shapes which have profound effects on engine performance are also investigated, especially the big end bore. The result of the analysis program based on the beam theory is compared and verified with that of FEM.