Waxy mutant wheat Tanikei A6599-4, which was induced from Tanikei A6099 (low-amylose line), exhibited a unique pasting curve with stable hot paste viscosity in the Rapid ViscoAnalyser (RVA) measurement. Analysis of the amylose content of reciprocal F1 seeds revealed the incomplete dominance and gene dosage effect in hexaploid wheat. In the dominance among multiple Wx-D1 alleles, the Wx-D1 allele of Tanikei A6099 partially dominated that of Tanikei A6599-4, and the allele of Tanikei A6599-4 partially dominated that of Tanikei H1881 (waxy line of amylose-free type). Genetic analysis using DH2 lines suggested that both the waxy character and stable hot paste viscosity of Tanikei A6599-4 are controlled by the same mutated Wx-D1 gene. We studied the pasting properties of Tanikei A6599-4 starch and compared them to those of other starches. At a low suspension concentration (6%), the peak viscosity of Tanikei A6599-4 was closer to that of Tanikei H1881 but the peak viscosity temperature was the same as that of Norin 61 (nonwaxy line). Addition of NaCl did not affect the starch pasting properties of Tanikei A6599-4, while potato starch which shows a more stable hot paste viscosity than cereal starches, was significantly affected by the NaCl treatment.