To provide a semiconductor wafer almost free from the formation of cracks or the like and a method of evaluating fracture strength which is capable of evaluating the difficulty of crack formation in the semiconductor wafer.

The grain sizes of abrasive materials to be used are optimized according to the kinds of the abrasive materials so that the means length of micro-cracks MC formed along the cleavage plane of a lapped surface 14b becomes ≤1 μm. Thereby, the frequency of occurrence of cracks or the like in a semiconductor wafer 14 is markedly suppressed. The most optimized particle size of the abrasive material for making the mean length of the micro-cracks MC within the range mentioned above is ≥#2,000 and ≤#3,000 when a green silicon carbide fine powder abrasive material is used and is ≥#1,200 and ≤#2,000 when an artificial abrasive material is used. The easiness of crack formation in the semiconductor wafer 14 can be evaluated by allowing a ball to naturally fall onto the main surface 14a of the semiconductor wafer 14 and measuring the height of a position from where the ball is allowed to fall and causes cracks on the semiconductor wafer 14. As the easiness of the crack formation in the semiconductor wafer 14 by an outer face can be quantitatively grasped by this method, it becomes possible to produce or select the semiconductor wafer 14 hard to be cracked.