Objective: A new method for the rapid detection of chloramphenicol in eggs was established, by preparing the aptamer magnetic bead complex, based on the mechanism of inhibiting the catalytic color reaction between the DNase and heme. Methods: The aptamer and DNase was combined through complementary base pairing, and it was combined with aptamer composite magnetic beads. Furthernore, by adding different concentrations of chloramphenicol solution, the DNase and chloramphenicol nucleic acid adaptation was disintegrated by dissociation of DNase catalytic chromogenic reaction combined with hemoglobin. Results: The linear range of chloramphenicol was 0.001~100.000 mg/kg, and the absorbance was linearly correlated with the concentration of chloramphenicol. The recoveries of the colorimetric method were 98.4%~101.1% at 5, 10, 25 mg/kg, and the relative standard deviations were all less than 10%. Conclusion: By introducing DNASE and magnetic nanoparticles, this method can effectively overcome the false positive results caused by non-specific adsorption of traditional rapid detection methods, and is more suitable for rapid detection of chloramphenicol residues in eggs.