Summary: It is important to estimate the aboveground biomass and carbon stocks of trees with non-conforming trunks in the forests of the central Congolese basin to plan resource management and to assess the contribution of these forests in mitigating the effects of climate change and, this within the framework of conservation at the scale of a reserve, that for Measuring, Reporting and Verifying forest carbon stocks within the framework of national strategies for the reduction of greenhouse gas emissions linked Deforestation and Forest Degradation (REDD+). This study aimed to set up a protocol for estimating the aerial biomass and the corresponding carbon stocks of trees with particular architecture in the Yasikia forest. To succeed, a dendrometric study was carried out for all trees with non-compliant trunks. Dendrometric data were collected on 189 trees divided into 9 families and 20 species. The results of this study show that it is preferable to use the equivalent diameter for a good estimate of the biomass because taking the diameter at the end of the buttress or above, underestimates the quantity of biomass for a tree with a trunk not compliant. The equation used to estimate the woody biomass from different diameters was that of Brown et al., (1989). The results of this study show that it is preferable to use the equivalent diameter for a good estimate of the biomass because taking the diameter at the end of the buttress or above, underestimates the quantity of biomass for a tree with a trunk not compliant. The equation used to estimate the woody biomass from different diameters was that of Brown et al., (1989). The results of this study show that it is preferable to use the equivalent diameter for a good estimate of the biomass because taking the diameter at the end of the buttress or above, underestimates the quantity of biomass for a tree with a trunk not compliant. The equation used to estimate the woody biomass from different diameters was that of Brown et al., (1989).