Thirteen kinds of common drug precursor chemicals were detected on the spot by transportable Raman spectrometer independently researched and developed. Changing analysis methods, such as the focal position of the instrument, analysis time, external light source, sample containers and the concentration of the analyte, the high quality Raman spectrums were obtained. The study shows that analysis method can be optimized to improve the detection efficiency, LOD(limit of detection)of 1-phenyl-2-acetone, toluene and chloroform was recorded for lower concentrations and the component contents of the mixture have a significant impact on the test results. Selecting the appropriate instrument conditions can be more effective and fast screening of precursor chemicals on site to provide help for those who are engaged in the anti-drug work．