Abstract: This paper describes the directional properties and the fatigue properties of rolled nodular cast iron sheets. It also contains comprehensive results on the influence of mechanical working, notch arid heat-treatment on the Charpy impact values within the temperature range of -87o and 1070℃. Results of investigation show that the occurrence of directional properties in rolled sheets is gradual, increasing with the increase in reduction in thickness by rolling. Ultimate tensile strength and elongation show more prominently the directional properties; while the proof stress σ0.2 does not give so great a difference in directions parallel and transverse to the direction of rolling. When the reduction in thickness is within 40%, there is an appreciable increase in Charpy impact value in all directions in the rolled sheet. Mechanical working improves the fatigue properties. At the reduction of 80%, the endurence limit in the rolling direction is raised by 27% as compared with the value in the cast condition. In the transverse direction, however, it is reduced by 3.3%. No well-ground surface is round on the fracture of the specimen. Heat-treatment raises the Charpy inpact values considerably. When there is no notch on the specimen, the impact values may be raised from 1/2 to 4 times by heat-treatment within the temperature range of -78 to 1070℃. Nodular cast iron is very sensitive to notch effect. Specimens with no notch give impact values 3.2-5.7 times those given by specimens having the standard Mesnager notch. Besides, specimens having the Mesnager notch yield results higher than those having the V-notch. Mechanical working also improves the Charpy impact value. When the reduction in cross-sectional area by forging reaches 93.5%, the impact value at 950℃ is 11.2 kg-m/sq. cm., which is 3 times the value of the cast material at the same temperature. Below room temperature, no cold-brittleness has been found in this highly-worked material up to the temperature of -820℃. The impact values remain within that temperature range at the values of 3.6-4.63 kg-m/sq. cm.