Three-point　bending　tests　were　conducted　at　various　low　temperatures　to　obtain　the　crack-tip　opening　displacement　(CTOD)　values　of　three　varieties　of　structural　steels　with　several　plate　thicknesses.　Parameters　of　the　crack　growth　resistance　curve　(Rcurve)　of　each　specimen　were　calibrated　by　regression　of　the　test　data　points　(CTOD　versus　crack　extension).　The　temperature　and　the　plate　thickness　had　great　effects　on　the　R-curve　shape　(flat　or　rising)　and　the　fracture　mode　(brittle　or　ductile).　In　a　design　process　of　a　steel　component,　an　initial　crack　is　assumed　according　to　its　fatigue　category.　Through　the　analyses　of　the　crack　driving　force　and　the　resistance,　a　practical　method　is　proposed　for　fracture　resistant　design　and　evaluation　of　flawless　or　flawed　steel　components　at　low　temperature.