The detection of Ethyl maltol (EM), Gallic acid (GA), and Rotenone in food is critical for preventing foodborne diseases. This study developed a new terbium-based metal-organic framework (Tb-MOF) for ultrasensitive multi-target detection in complex food matrices leveraging competitive absorption mechanism. It is the first MOF-based sensor detecting EM with LOD of 0.047 μM, lower than those of most reported chromatographic techniques. Furthermore, it could be used to detect GA and Rotenone with LOD of 0.105 nM for GA and 0.007 μM for Rotenone, which were the lowest LOD among fluorescent sensors reported to date for GA and Rotenone. The sensor could be used to detect EM, GA, and Rotenone in real samples including infant formula, edible oils, and fresh fish, and exhibited practical reliability with 98-103 % recoveries and RSD < 3 %.