The general objective is to characterize the structure of two aggregates of.Jlllbernardia seretii in the Southern block of the forest reserve of Yoko. A surface of 2 ha each of 100 X 200 m of with dimensions subdivided into 10 placettes of20 X 200 m inside of which, all individuals of Julbernardia seretii to dbhz 10 ern and those with lcm Sdbh < 10 em were measured to 1, 30 ern of the ground and positioned by the catch of co-ordinates X, y. the individuals of other species were simply inventoried and their measured circumferences. With the exit of the floristic inventory. 1296 individuals divided in 96 species and 32 families whose 47 individuals of Julbernardia seretii were inventoried. The "Guineo-congolais" element, the "sarcochores" and the "mesophanerophytes' are respectively the types of phytogeographical distribution. "diasporas" and biological most represented. The individuals of various species inventoried within two aggregates are statistically the same ones with regard to the density, but significantly different for the occupation from the ground, but they are statistically the same ones in particular for the individuals of Julbernardia seretii. The diametric structure of the individuals of various inventoried species presents a curve in the shape of "J reversed" and statistically different within two aggregates while it is statistically the same one in particular for the individuals of Julbernardia seretii. The distribution of the individuals acquired regenerates is independent compared to that of the groves.