Velvet maple (Acer velutinum) is one of the woody species in the Hyrcanian forests. In this study, the relationship between height and diameter of velvet maple was surveyed. A complete list of the selected height- diameter models was used and nineteen candidate models were considered. Various criteria were chosen and applied to evaluate the predictive performance of the models. These criteria include Akaike information criterion (AIC), Bayesian information criterion (BIC), root mean square error (RMSE), mean error (ME), and adjusted coefficient of determination (R 2 ). Fitting of nineteen height-diameter models using nonlinear least square regression showed that all of the parameters in models were significant ( P < 0.01). The results of goodness of fit for the calibration and k-fold validation and the performance criteria (RMSE, ME, AIC, R 2 adj and BIC) showed that R 2 adj ranged from 0.743 (model 8) to 0.8592 (model 11) and RMSE from 2.6983 (model 11) to 10.1897 (model 9). The range of ME among the models is from -7.0787 (model 9) up to 0.063m (model 7). By considering the AIC for each model it is evident that model (11) and model (9) have the lowest and highest values, respectively. Plotting the residuals showed that for all these models the residuals were randomly distributed and the models had heterogeneous residuals. According to the results, models (11), (14), (13), (15) and (12) had a better fitness compared to other models. Among these models, model (11) was the best model for predicting total height of Acer velutinum trees in this region . Covering an area of approximately 1.85 million ha, the Hyrcanian forests account for approximately 15% of the Iranian forests and 1.1% of the country's total area. These forests range from sea level up to an elevation of 2,800 m and comprise various for - est types including no less than 80 woody species (trees and shrubs). Oriental beech ( Fagus orientalis Lipsky ), oak ( castaneifolia), maple ( velutinum), hornbeam ( Carpinus betolus) and al - der ( subcordata) are among the main tree species in these forests. The Hyrcanian forests have been forestland since the third geological era and are considered to belong to the oldest forests in the