A simple and sensitive method for extraction and detection of morphine in urine was described. The continuous extraction method showed a virtually complete recovervy of morphine and prevented the formation of emulsion unavoidable in the extraction by shaking. The hydrolysis condition which led to liberation of most of morphine from the conjugates in urine was found to be that of heating for 30 minutes, in the 15% hydrochloric acid concentration. This procedure was simple, but afforded the comparable result to that of sealed tube hydrolysis in the 5% hydrochloric acid concentration. Double thin-layer chromatographic method was successfully applied first to the separation of morphine from a large amount of impurtities in the urine extract using thicker plate (1 mm.) and then to the final detection of morphine using ordinary one (0.25 mm.).