The HPLC method for morphine content determination in poppy straw has heen developed and validated. The method validation involved reproducibility and the following parameters of accuracy: selectivity and specificity, linearity and limits of detection and determination, interferences and recovery. The method was used to determine the morphine content in plant resources classified by the Law on "Neutralization of drug abuse" as a intoxicating agent from group I-N, in the content range of 0.02 to 0.27%. The determination was established for 80 samples of plant resources from the whole country of Poland.