ABSTRACT
<p><b>OBJECTIVE</b>To provide scientific basis for quality evaluation by investigating the influential factors of the volatile oil and main constituent content in Pogostemon cablin.</p><p><b>METHOD</b>Several experiments were carried out to test different habitats, collection periods, processing methods, the level of spreading manure and using agricultural chemical with the volatile oil assay of pharmacopoeia and GC-MS method.</p><p><b>RESULT</b>The effect of different habitats, collection periods, processing methods on volatile oil and main constituent content was shown significantly.</p><p><b>CONCLUSION</b>Such factors as different habitats, collection periods, processing methods should be taken into account when the quality standard of medicinal materials was made.</p>