The Amazon is one of the most complex ecosystems on earth, where it is interrelated the flora, fauna (macro and micro), soil, water and air, maintaining a balanced environment, through the fertility of the soil. That is why this work has been done with the aim to determine the density, biomass and distribution of the macroinvertebrates of the soil in plantations of cacao (Theobroma cacao L.), in two sessions (dry and rainy season). We selected four different agro-ecological units (CHI, SLD, MET and CMP). Where it used the methodology Tropical Soil Biology and Fertility (TSBF), ranked five sampling points along a separated from 10 m. In each one of them was placed a frame of 25 x 25 cm. getting a pit and/with layers of leaf litter, 0-10 cm. 10-20 cm and 20-30 cm. The entomology laboratory of the Research Institute of the Peruvian Amazon identified and preserved the samples obtained in the...