Northern Iran especially Alborz Mountain range is one of the most important floristic regions of Iran, which has high medicinal plant biodiversity. Research areas were located between the northern part of the Alborz Mountains range and south of the Caspian Sea in northern Iran, west of the Mediterranean. Selection of rangelands for ecological survey was carried out according to the climate diversity of Amol County in Mazandaran province during 2018 growing season. Three altitude in the regions including Rineh (1800 m above mean sea level), Polur (2300 m AMSL) and Lar Plain (2800 m AMSL) for each herbal medicinal plant (Sophora alopecuriodes, Peganum harmala and Ziziphora clinopodioides Lam) were chosen as treatment. The results showed that plant fresh weight and plant dry matter of Peganum harmala, Sophora alopecuriodes and Ziziphora clinopodioides was decreased with enhance of altitude from sea level. Essential oil yield of Peganum harmala and Sophora alopecuriodes enhanced by increase of altitude, but for Ziziphora clinopodioidest, with increase of altitude the essential oil yield was decreased. In Peganum harmala, only benzaldehyd 2-amino was enhanced with increase of altitude from 1800 m to 2800 m AMSL, but eicosane was decreased by altitude increasing. For Sophora alopecuriodes the most amount of sophoramine and adenocarpine was obtained in 1800 m above sea level, but sophocarpine and vinylphenol shows the highest rates in 2800 m AMSL. For Ziziphora clinopodioides, the highest amount of alpha.-thujene, camphene and sabinene was observed in altitude of 1800 m above sea level. But, alpha.-pinene, 2-beta.-pinene, beta.-myrcene and 3-octanol in altitude of 2800 m AMSL demonstrated higher rates. As a result, natural ecosystems, altitude above sea level are among the main determinants of the qualitative and plant quantitative parameters of medicinal plants.