13C1-N-Acetylimidazole (—CO13CH3) was synthesized by reacting 2-13C1-acetic acid with N,N'-carbonyldiimidazole, and then reacted with p-aminophenol to obtain 13C1-paracetamol (—CO13CH3). The influences of factors such as temperature and reaction time on the yield of products were investigated. The results showed that the optimal reaction temperature and time for the product synthesis were 40 ℃ and 12 h, respectively. The product was characterized by GC-MS, FTIR, 1HNMR and 13CNMR. The results showed that paracetamol contained one 13C atoms. The chemical purity was better than 99% and 13C enrichment was more than 98.7 atom%. The yield of product was 87%. Synthetic product can be used as an isotope internal standard in quantitative analysis testing.