An experimental study was carried out to determine the influence of different superficial gas velocities on the agglomerates of cohesive particles. The probability of agglomerate coalescence and breakup is proposed on the basis of the principle of force balance. Theoretical analysis shows that the higher superficial gas velocity and fluid density, the lower the particle cohesion, and that collisions between small and large agglomerates arc advantageous for the agglomerating fluidization of cohesive particles. The average agglomerate size estimated by the model of force balance decreases with increasing superficial gas velocity, which is in agreement with experimental data.