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A dual-emission fluorescent (FL) probe was constructed by coordinating Cu2+ of copper metal–organic frameworks (Cu-MOFs) with − COO− group of carbon dots (CDs) for pesticide thiophanate-methyl (TM) determination. TM was recognized by organic ligands (H2BDC and H2BDC-NH2) of Cu-MOFs via π stacking. Due to the higher affinity of Cu2+ to TM than ligands and CDs, TM chelated with Cu2+ to form TM-Cu complex. Thus coordination of Cu-MOFs was damaged and the ligands were released resulting in the FL intensity increase of Cu-MOFs (F430). And also CDs were released from CDs@Cu-MOFs hybrids and electron transfer from CDs to CuMOFs was inhibited, leading to the FL intensity increase of CDs (F600). The FL intensity ratio (F430/F600) showed a good linear relationship with TM concentrations of 0.0307–0.769 μmol L−1 with a limit of detection (LOD) of ~ 3.67 nmol L−1. The probe was successfully applied to detect TM in spiked food samples with satisfactory recoveries of 93.1–113%. Additionally, visual detection of TM was achieved according to the fluorescence color variation from blue to carmine, indicating promising application of CDs@Cu-MOFs probe. [ABSTRACT FROM AUTHOR]