<p>This study combined experimental examination and Pandat simulation to investigate the microstructural development of the 11wt.%Al-3wt.%Mg-0.25wt.%Si-Zn coating on steel. The examination revealed that the coating microstructure comprised an Fcc-Al dendrite framework and an interdendritic region containing primarily a lamellar MgZn₂/Hcp-Zn mixture, some blocky MnZn₂ particles and some fine (Mg,Al)₂Si platelets. The Pandat simulation revealed that the coating solidified in four stages with the change of the remaining liquid composition: I. 424.4−360.2°C: Liquid → primary Fcc-Al + Liquid' (5.46%Al-3.45%Mg-0.288%Si-Zn); II. 360.2−356.9°C: Liquid' → Fcc-Al + MgZn₂ + Liquid'' (5.22%Al-3.39%Mg-0.294%Si-Zn); III. 356.9−335.9°C: Liquid'' → Fcc-Al + MgZn₂ + (Mg,Al)₂Si + Liquid''' (3.65%Al-2.94%Mg-0.209%Si-Zn); IV. At 335.9°C: Liquid''' → Fcc-Al + Hcp-Zn/MgZn₂ + (Mg,Al)₂Si. The volume percentages of various solid phases formed during solidification were also computed, with the Fcc-Al eventually occupying 40 mol.% of the coating, the lamellar MgZn₂/Hcp-Zn mixture 54.1 mol.% (12.6 mol.% MgZn₂ + 41.5 mol.% Hcp-Zn), the blocky MgZn₂ particles 4.47 mol.% and the fine (Mg,Al)Si₂ platelets 1.43 mol.%. The formation mechanisms of the various phases and microstructural features are also discussed.</p>