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Ractopamine is a synthetic βreceptor agonist that can be used to feed livestock to improve lean meat yield. Ractopamine can cause health problems and even endanger life if eaten from livestock, poultry or viscera. Traditional ractopamine detection cycle is long, time-consuming and laborious, which is not conducive to the actual large-scale promotion of use. In some slaughterhouses, sampling inspection is often used for testing which is a serious lag. A portable rapid screening device for ractopamine in pork was developed. The device mainly included spectra acquisition module, light source module, control module, power supply and computer. Based on NI LabVIEW software development tool, G language was used to write the control software of intelligent and rapid detection of pork “clenbuterol”. Firstly, ractopamine was extracted from pork by ethyl acetate in alkaline environment, and detected by SERS method. The effects of several different concentrations of NaCl aqueous solutions as aggregators on SERS spectra of ractopamine were compared. The results showed that 1mol/L NaCl as aggregator had the best enhancement effect. Secondly, the effect of droplet evaporation on Raman signal was compared. The results showed that the Raman signal was better after 4s. Then, pork samples with different ractopamine contents (1μg/g, 2μg/g, 4μg/g, 6μg/g, 8μg/g and 10μg/g) were prepared for quantitative analysis. Automatic Whittaker fitting algorithm (AWF) was used for preprocessing, and the fluorescence background contained in the original Raman spectrum was deducted. A linear regression model was established between SERS intensity at 836cm-1 and ractopamine content in pork samples. The results showed that the model has a good linear relationship, the correlation coefficient R2 was 0.99, and the root mean square error was 0.178μg/g. Finally, a batch of pork samples with the same ractopamine content were prepared, and the device was used to detect ractopamine in pork. The predicted values had a good linear relationship with the standard physicochemical values of the samples, the correlation coefficient R2 was 0.99, and the root mean square error was 0.317μg/g. The device was simple, portable, inexpensive, and the detection time was less than 1h. The detection limit was 1μg/g. It can be used for rapid screening of ractopamine in pork.