Datura metel (Solanaceae) from south Lebanon. The different parts of this plant contain the tropane alkaloids atropine (AT) and scopolamine (SC), which are naturally muscarinic receptor antagonists. A method has been developed for the extraction and HPLC-UV analysis of the AT and SC in different parts of D. metel, namely seeds, capsule, leaf, and stem. This analytical method was validated and gave a good detection response with linearity over a dynamic range of 0.03‑0.17 mg mL−1 and recovery in the range of 93.9–108.76%. Limit of detection (LOD) and limit of quantification (LOQ) values were 32 and 98 µg.mL-1 for atropine and 31 and 93 µg.mL-1 for scopolamine, allowing a reliable quantitation of the target alkaloids. The solvent system Methanol/acetonitrile was the better choice for extracting tropane alkaloids from different Datura parts. Capsule parts of the plant accumulate the highest amount of scopolamine, while seeds accumulate the higher amount of atropine. Briefly, the order of scopolamine concentrations in Datura metel parts, from Lebanon, was in capsules ˃ seeds ˃ leaves ˃ stems and for atropine, the concentrations were in seeds ˃ capsules ˃ stems ˃ leaves.