As the basic units of proteins, the importance of amino acids in organisms is self-evident and therefore detection of the concentration of amino acids is significant in monitoring human health. Herein, a dual-responsive Eu³⁺-functionalized metal–organic framework (MOFs) luminescent film (1@SA) was designed and prepared, which not only realizes the simultaneous detection of aspartic acid (Asp) and arginine (Arg) but also has the possibility of being applied in anti-counterfeiting. A portable film sensor is obtained through the cross-linking and solidification of Eu³⁺ ions and sodium alginate (SA) hydrogel containing uniformly dispersed MOFs. The MOF used in this work is a zinc metal–organic framework (ZnMOF) comprising uncoordinated carboxyl groups that can provide binding sites for Eu³⁺ ions. Moreover, it is found that the sensor shows unique fluorescence changes under the stimulation of an acidic environment. Therefore, the quantitative detection of Asp and Arg by 1@SA can be achieved, and optical anti-counterfeiting platforms are also designed according to the diversity of fluorescence changes. The new strategy proposed in this work may broaden the scope of lanthanide fluorescence films used in optical fields.