Aluminum‑zinc‑magnesium (Al-Zn-Mg) alloy that is fabricated by using traditional plastic processing is not suitable for laser additive manufacturing due to its tendency to crack. To design aluminum alloy with low hot cracking tendency and is suitable for laser additive manufacturing, an aluminum‑zinc‑magnesium‑scandium (Al-Zn-Mg-Sc) system is proposed in this study. A theoretical model is used to predict the hot cracking susceptibility of this system. The optimized alloy composition is Al-6.5Zn-2.2 Mg-0.4Sc and its formability during laser melting deposition (LMD) is then investigated. An anisotropic microstructure is observed in the alloy: columnar grains with a [001]//Z texture in the building plane and equiaxed grains in the scanning plane. Pores are the main metallurgical processing defects, but a few hot cracks can be seen in the laser melted (Al-Zn-Mg-Sc) alloy. The mechanical properties can be significantly improved through heat treatment: the ultimate tensile strength of the alloy is increased from 258.7 MPa to 390.3 MPa, and elongation of the alloy is increased from 13.1% to 29.6% after solution and aging treatments, thus indicating that the alloy has good plasticity.