PURPOSE: To carry out defrosting and fermentation of frozen bread dough having quality equivalent to a product obtained by an ordinary bread dough production method by defrosting frozen bread dough under specific conditions, preheating the dough and further retaining the dough under definite conditions.

CONSTITUTION: Frozen bread dough is defrosted at -5 to +10°C, 90 to 100% humidity and ≤0.2m/s air rate for 10min to 72hr. Then the dough is pre-heated at 90-100% humidity and ≤0.2m/s air rate and 15 to 20°C for 1hr and 20min to 2hr and 10min. Then the conditions of 22-38°C, 65-100% humidity, ≤2m/s air rate is retained for 20min to 3hr to carry out defrosting and fermentation of the frozen bread dough.