The preparation of large-scale Cu—Al—Ni shape memory alloys with excellent microstructure and texture is a significant challenge in this field. In this study, large-scale Cu—Al—Ni shape memory alloy (SMA) slabs with good surface quality and strong orientation were prepared by the horizontal continuous casting (HCC). The microstructure and mechanical properties were compared with the ordinary casting (OC) Cu—Al—Ni alloy. The results showed that the microstructure of OC Cu—Al—Ni alloy was equiaxed grains with randomly orientation, which had no obvious superelasticity. The alloys produced by HCC had herringbone grains with strong orientation near ❬100❭ and the cumulative tensile superelasticity of 4.58%. The superelasticity of the alloy produced by HCC has been improved by 4–5 times. This work has preliminarily realized the production of large-scale Cu—Al—Ni SMA slab with good superelasticity, which lays a foundation for expanding the industrial production and application of Cu-based SMAs.