Elucidating the dynamic relationship between aerosols and water vapor is crucial for revealing atmospheric processes, assessing environmental changes, and predicting climate system responses. Based on continuous lidar observations in Beijing during 2023, this study analyzed the correlation and variation patterns between aerosol backscatter ratio and water vapor mixing ratio profiles. Results reveal the consistency in the distribution and co-variation characteristics of aerosols and water vapor, where the correlation is significantly influenced by the season and both the heights and sources of air masses. Statistical analysis of the data shows that within the vertical range of 0.2?1 km, the correlation coefficient between the aerosol backscatter and water vapor mixing ratios exceeds 0.9, indicating a significant correlation. Notably, air masses from the northwest exhibit a higher correlation between these two factors as compared with other sources. Layered statistical results indicate that the correlation between aerosols and water vapor gradually weakens with increasing height. The seasonal statistics indicate that the correlation between the two profiles during autumn and winter is higher than that during spring and summer. These findings provide a new understanding of the interaction between aerosols and water vapor in the atmosphere, which is of great significance for improving atmospheric models and climate change predictions.