The wide crystallization temperature range of Al-Mg alloys is a key factor for the surface defect formation during continuous casting and rolling process. To reduce the crystallization temperature range of the alloy, the influences of trace Zn, Si, Zr and Ti elements on the microstructure and properties of Al-2Mg-0.5Mn alloy were investigated. The X-ray photoelectron spectroscopy, atomic force microscopy, scanning and transmission electron microscopy were used for microstructural characterization. The Ti and Zr additions could refine the grain size and improve the strength of the Al-Mg-Mn alloy by forming Al₃Ti and Al₃Zr in the alloy, while the crystallization temperature ranges of these alloys were wider. It was revealed that Zn and Si additions could form new secondary phases with Mg in the alloy, thus reducing the actual Mg content during later eutectic solidification process. Therefore, the crystallization temperature range of Al-2Mg-0.5Mn-0.2Zn-0.2Si alloy was narrower than that of Al-2Mg-0.5Mn alloy. The mechanical properties and corrosion resistance of Al-2Mg-0.5Mn alloy were also improved by the additions of Zn and Si.