A rapid method with thin layer chromatography (TLC) combined with surface enhanced Raman spectroscopy (SERS) for detection of the chemical drugs illegally added into compound product of Eucommiae capsule is developed. Chemical drugs added in simulation of positive drugs are separated by TLC initially, using toluene-ethyl acetate-ethanol-strong aqua (12∶3∶3∶0.2) as the mobile phase, and then the SERS method is used to analyze the separated chemical drug spots. The characteristic peaks of Raman spectra of the chemical drugs added into the compound product of Eucommiae capsule obtained by TLC-SERS method are nearly consistent with the reference substance. This TLC- SERS method can be used for detection of chemical drugs illegally added into compound anti-hypertensive Chinese patent medicine quickly, accurately and sensitively.