Abstract: To clarify the function mechanism of antisense - thioredoxin s (anti-trxs) gene in transgenic wheat with pre-harvest resistant sprouting characteristic, the thioredoxin h and amylase activities, starch and soluble sugar contents in transgenic line and non-transgenic cultivar ‘Yumai 34’ were detected during seed germination stage. The results indicated that the activities of thioredoxin h, α- amylase and β-amylase were lowered significantly and the velocities of starch degradation and soluble sugar production decreased distinctly. During germinating days 1-5d, the activities of thioredoxin h, α- amylase and β-amylase were 24.5%, 40.4% and 23.1% lower than non-transgenic seeds, respectively. The velocities of starch degradation and soluble sugar production decreased by 23.7% and 23%, respectively.