In this study the effect of altitude (in two provinces of Mazandaran and Golestan) on some morphological and biochemical properties of the stems, flowers and root of nettle plant was examined. Sampling was performed at the flowering time of plant. Extraction and identification of active ingredients were performed by using spectrophotometer and HPLC methods. This research was conducted based on completely randomized design by using statistical analysis software (SAS, 9.1). Results that altitude did not show significant effect on morphological properties, but in general it can be said that the height 1450m above the sea level in both provinces was the best height for morphological characteristics. Maximum size of stem diameter (7.05cm), root diameter (5.01cm), root length (31.1cm) and number of inflorescence (54.2) were observed in Golestan province at the altitude of 1450m and the highest size of inflorescence (5.52cm) in the Mazandaran province was related to the altitude of 1450m above the sea levels. The amount of total phenol, total flavonoids, Chlorogenic acid, caffeic acid and rutin in the stem and leaf, nettle root increased with increasing the height, so that the largest amount of total phenol (3.38 and 1.28 mg/g), total flavonoids (3.98 and 2.53 mg/g), Chlorogenic Acid (0.3 and 0.13 mg/g), caffeic acid (0.065 and 0.021 mg/g) and rutin (0.37 mg/g) were observed in stem, flower and root plant at altitude of 2250 m in leh koh region of Mazandaran province. Results showed that positive correlations exist between total phenol and flavonoid content and height of sea level. Many of morphological parameters such as stem diameter, root diameter, root length and number of inflorescence in Golestan province increased with increasing altitude up to 1450 m and the size of inflorescence in Mazandaran province in the same height showed the highest value.