Key message <p>The proposed methodology represents the first work to estimate the AGB of hazelnut trees by TLS and for representing the different woody structures. Potential application for carbon credit certification.</p> Abstract <p>Accurate estimation of Aboveground Biomass (AGB) in tree orchards is essential for assessing productivity and carbon sequestration. The objective of this research was to develop a method for estimating the total AGB of hazelnut trees (<i>Corylus avellana</i> L.) of different ages, based on TLS technology integrated with the MATLAB TreeQSM algorithm combined with destructive measurements of coarse (Ø ≥ 4&#xa0;mm) and fine (Ø ≤ 4&#xa0;mm) structures in order to overcome the estimation limitations of the algorithm. This study, the first contribution on hazelnuts, proposed an integrated approach for estimating AGB, combining Laser Imaging Detection and Ranging (LiDAR) based on TLS, computational analysis in MATLAB^®, and targeted destructive and manual measurements to derive key dendrometric parameters. Results revealed statistically significant differences in fine structure biomass between 15-year-old (22.56 ± 4.15&#xa0;kg) and 20-year-old trees (34.69 ± 10.80&#xa0;kg), confirming the use of TLS, combined with MATLAB processing and limited destructive measurements, as an appropriate technology for biomass estimation and for representing the different structures. TreeQSM algorithm was found to be highly reliable in estimating the length of branches with Ø ≤ 4&#xa0;mm (R² = 0.95) and in estimating the volume of woody structures Ø ≥ 4&#xa0;mm.&#xa0;The proposed methodology provides valuable support for AGB estimation in tree crops by integrating TLS-based modelling with empirical measurements. A key outcome of this study is the potential application of the proposed methodology for carbon credit certification. Future research should extend to the different stages of tree growth to consider the growth dynamics induced by agronomic management.</p>