Fe–B magnetic particles doped GdBa2Cu3O7-δ superconducting bulks were fabricated by using the top-seeded melt growth method. 10 wt% Ag2O or equivalent 9.31 wt% nano–Ag particles (50nm in diameter) were added into the precursors before the sample preparation. The Fe–B doped GdBa2Cu3O7-δ/nano–Ag showed poorer mechanical properties with an obviously porous/cracked structure than the GdBa2Cu3O7-δ/Ag2O one especially at the bottom part of the bulk. In the GdBa2Cu3O7-δ/Ag2O bulk, doped Fe element is mainly wrapped or attached by Ag particles. In contrast, the Fe element prefers to substitute on the Cu sites in the GdBa2Cu3O7-δ/nano–Ag bulk due to less protection from Ag particle. The microstructure and superconducting properties were investigated in these two series samples.