This study Aims to evaluate the vegetation structure and diversity of woody species in the mountain forest of Mount Kupe (South-West Cameroon) between 1 500 and 2064 m and to appreciate the index values obtained with those of the tropic, Malagasy and Neotropical region of the world. The basic data have been obtained on inventory of 2.125-ha plot taking into account all trees whose diameter at breast height (DBH) ? 10 cm. The parameters of floristic diversity were calculated using the standard methodology. A total of 1819 individuals belonging to 136 species, 83 genera and 42 families were inventoried, with a total basal area of 193.75 m²/hectar. Most individuals (trees) had a height between 10 and 15 m with diameter between 15 and 85 cm, but relatively a significant number of individuals (10) reached even higher values, up to 30 m height and 165 cm of diameter. The five most important families in terms of density, diversity and dominance were Rubiaceae, Clusiaceae, Meliaceae, Malvaceae and Leguminosae.They represent 48.29 % of the Family Important Value (FIV). The specific composition revealed that 10 species dominate the montane forest, 7.35 % of species represent 43.39 % of the Index of Value Importance (IVI). They are Garcinia smeathmannii, Cola acuminata, Zenkerella citrina, Trichilia procera, Carapa oreophila, Macaranga occidentalis, Santiria trimera, Trichilia rubescens, Tabenaemontana crassa and Drypetes staudtii. A fraction of species (37) then 27.21 % is represented by one individual. In conclusion, the Kupe montane forest is marked down substantially to the lowland forest. The family of Leguminosae which dominate in these levels is occurring among the 10 important families in FIV (18.68) ; they come in the 5th position. The Rubiaceae occupies 1st position in relative diversity and 1st position in FIV mark in this altitudinal stretch.

Keywords: Highlands, montane forest, plant diversity, species, vegetation structure