Herein, we report a novel approach to AS1411-templated formation of fluorescent copper nanomaterials and their application to melamine detection. Fluorescent copper nanomaterials were formed at room temperature by using AS1411 as a template and ascorbic acid as reductant. However, the fluorescence intensity decreased obviously in the presence of melamine. Under the optimized conditions, the quenching fluorescence intensities of copper nanomaterials showed a good linear relationship with the concentration of melamine in the range of 50 μ mol/L–120 μ mol/L, and the correlation coefficient was 0.9823. In addition, the method was successfully applied in the detection of melamine in milk samples. This method was cost-effective and convenient without any labels or complicated operations. Thus, this work successfully develops the capping AS1411 scaffolds of copper nanomaterials detection of melamine.