The study of ecological characteristics of Camellia sinensis var. assamica (Miang tea garden) was conducted in Chiang Mai, Lampang, Phrae and Nan Province northern of Thailand. Plants biodiversity were studied and related to factors such as soil property and climatic data. Basic data will be managed with “Miang tea garden”. Four villages were chosen for representative of Miang tea garden, Ban Lao village at Chiang Mai province, Pa miang village at Lampang province, Mae lua village at Phrae province and Sri napan village at Nan province. Five plots of each village were interviewed farmers. Vegetation sample plot was surveyed of each miang tea garden. Soil sampling were collected surface soil (0-5 cm) and sub-surface soil (20-25 cm). Soil samples were analyzed soil chemical and physical property. Result shown that; Species composition in miang tea garden at Four viilages found vegetation species around 14 to 22species, 11 to 22 genus and 11-22 familys and Shannon-Weiner index were 0.16 to 1.24. Soil Acid value of both sites were high and sub-surface soil was higher than surface soil. Soil fertility at surface soil was higher than sub-surface soil. The percentage of clay mineral were high almost of both sites. Soil hardness at sub-surface soil was higher than surface soil and inverse variation with soil moisture. Annual rainfall at Nan province and Phrae province were 1,169.3 to 1,260.6 mm/year respectively.