Abstract: Using sprouting sensitive variety, AT265, the field prevention and cure experiment was undertaken with the natural sprouting depressor -YSR, obtained by the authors. Using colorimetric determination of 3, 5-dinitro-salicylic acid, α-amylase was tested for the seeds treated with different concentration YSR during germination. The results were as follows: the best prevention and cure time of YSR was 2d before harvesting, inhibiting rate was 75.9%, and YSR had no side effect to seed using value. α-amylase content fallen rapidly with increasing of YSR concentration. This proved that YSR could inhibit sprouting through lowering α-amylase during germination in wheat gains.