We investigate the phase separation of a binary polymer blend-particle system under fluctuating fields. Our results show that the disordered stochastic field would drive the formation of ordered stripe structures, and the domain growth dynamics is intensively affected by both the blend-particle coupling effect and stochastic motion of driven particles. Particularly, for large fluctuating force and enough particle number, the domain morphology shows the better orientational stripe patterns in two-dimensional case, and the cylindrical structure along the fluctuating force direction in three-dimensional case. In addition, the particle mobility is also one of the crucial factors dominating the domain growth at the late stage. (C) 2003 American Institute of Physics.