Grain growth behavior in reactive spray deposited Al–Mg–Mn alloy 5083 and 5083 + Zr was quantitatively studied at 500, 530, and 560 °C. Results show that reactive spray deposited 5083 processed using N2–5% O2, in which no significant volume fraction of oxide particles was found, experienced significant grain growth when annealed at 500, 530, and 560 °C following recrystallization. On the other hand, reactive spray deposited 5083 atomized with N2–10% O2 and 5083 + Zr atomized with N2–5% O2 exhibited very slow grain growth below 530 °C and limited grain growth at 560 °C. This behavior is attributed to the retardation effect of the secondary phase particles that were formed in these alloys.