The competitive behaviors between recrystallization and transformation during annealing in dual phase high-strength steels are studied both by experiments and by computer simulations. The Monte Carlo code was applied to simulate such competing behavior, explained the experimental results, as follows. (1) The progress of the transformation is affected by the starting point of the transformation in the course of recrystallization. Namely, if the transformation starts at the later stage of recrystallization, the n-value in JMAK equation is relatively high. (2) If the stored energy (driving force) of the transformation is above 5 times larger than that of the recrystallization, the effect of the stored energy is quite small. (3) If the number of nuclei were increased, the transformation proceeds a little faster, and then the transformed microstructures are significantly refined. When the transformation initiates at the early stage of the recrystallization, the number of nuclei can be increased by nucleation from the deformed matrix compared with the one from fully recrystallized matrix.