Biogenic volatile organic compounds (BVOCs) are important precursors of ozone (O₃) formation. A rational understanding of the contribution of BVOCs to O₃ pollution is highly significant for regional air quality and environmental management. This study estimated the BVOCs emission intensity and their contribution to O₃ concentration in Shaanxi Province in 2023 based on the MEGANv3.2 and CMAQ models, combined with WRF-simulated meteorological fields and MODIS leaf area index (LAI) data. The results showed that: The WRF model accurately simulated temperature trends and radiation, meeting the requirements for regional meteorological input; but the reliability of wind speed and humidity simulations requires further improvement. The CMAQ-simulated O₃ concentrations exhibited a significant correlation with measured values, though the overall concentrations were underestimated. After applying a regression-derived correction factor of 1.15, the simulated results aligned well with observations. The average BVOCs emission intensity across the province was 3.37t/(km²·a). High-emission areas were primarily distributed in the Qinba Mountains of southern Shaanxi (5.77t/(km²·a)) and the Qiaoshan and Huanglongshan areas of Yan'an (4.74t/(km²·a)), both of which are regions with high natural forest coverage. Low-emission areas were mainly located in the grassland regions of Yulin (0.46t/(km²·a)), the forest-steppe transition zone in northern Yan'an (0.97t/(km²·a)), and the Guanzhong Basin (2.21t/(km²·a)). BVOC emissions exhibited distinct monthly and diurnal variations, peaking in July (0.99t/km²) annually and at 14:00 (local time) daily with a maximum value of 98.65kg/km². Isoprene (ISOP), monoterpenes (TERP), and sesquiterpenes (SESQ) were the main BVOC components, accounting for 37.39%, 28.49%, and 3.56%, respectively, with variation trends similar to total BVOCs. Trees and shrubs were the dominant sources, contributing 51% and 35%, respectively. In July, BVOCs contributed an average of 9.9% to the monthly mean maximum 8-hour O₃ concentration in Shaanxi Province, with ISOP and TERP accounting for 60.5% and 14.8% of this contribution, respectively. In October, the average contribution of BVOCs to the monthly mean maximum 8-hour ozone concentration decreased to 3.1%.