Packaging material is similar to food and is affected by a variety of factors in the process of specimen detection. Pre-treatment of samples plays a key role in all these analysis procedures. By taking the bisphenol A substances in the food simulates as the research objectives, the detection method of harmful substance migration in 3-piece can was carefully studied. The sample pre-treatments of all of these three kinds of simulates, including 10% and 50% ethanol in volume fraction, and 3% acetic acid in mass fraction were explored