Based on the DEFORM-3D software, a finite element model considering macro-micro forming of rib-web component isothermal local loading has been established. The forming process of H-shaped component and the effects of loading mode and sequence, position of die partition, and process parameters on the filling of ribs and primary a-phase grain size have been investigated. The results show that the position of die partition has a significant effect on the filling of rib, the rib will be filled better and the distribution of primary a-phase grain size is more uniform when the die is partitioned along the rib. Comparing with only by local loading forming mode and through local loading combining with sizing forming, the deformation is more uniform and the difference of filling depths between ribs is smaller with better distribution of streamline. Enlarging the fillet radius between rib and web, the rib is filled well and the filling depth difference between transverse and longitudinal ribs increases. With the increase of loading speed, the filling depth of rib decreases, and the primary a-phase grain size decreases, but the distribution of primary a-phase grain size is more non-uniform. But the loading sequence has little effect on primary a-phase grain size