The invention discloses a method of simultaneously detecting free CML and 5-HMF in a liquid or semi-solid condiment. The method comprises steps: firstly, detection pretreatment is carried out on freeCML and 5-HMF in a liquid or semi-solid condiment system; and a to-be-detected sample after pretreatment is subjected to simultaneous detection of CML and 5-HMF. The pretreatment step comprises substeps: (1) water is added to the to-be-detected liquid or semi-solid condiment for dilution, and uniform mixing and centrifugation are carried out; (2) supernatant after centrifugation is taken, a PolyClean X-MCX solid phase extraction column is used for purification, water is added for elution, an ammonia-methanol solution is then added for elution, and an eluent is gathered; and (3) the eluent is dried and is re-dissolved in the methanol-water solution, and through microfiltration membrane treatment, the to-be-detected sample is prepared. The method has the characteristics that matrix effects are reduced, interference is eliminated, the operation is simple and efficient, safety and reliability are achieved, the detection efficiency is high and the like.