Riverine carbon dioxide (CO₂) emission is an essential component of the global carbon budget. Here, environmental variables were measured in the Yue River of the upper Han River draining to the Yangtze River in the dry season (December 2016) and the rainy season (June 2017) to explore the dynamics and driving factors of the river pCO₂ in the low order streams. Results reveal that around 87% of samples have pCO₂ levels that are supersaturated. Riverine pCO₂ ranges from 135 μatm to 5960 μatm and shows a significant seasonal difference. The pCO₂ level constantly increases with the stream order increases. Correlation analysis shows that pCO₂ is positively related to construction and farmland proportion and TN, TP, DOC concentrations in the low order streams, while is negatively related to the forest land proportion, DO concentration and slope. The low order stream pCO₂ dynamics are driven by anthropogenic activities and environmental factors, as the influence of the former decreases with the stream order increases. We further develop multiple regression models to fit the different order streams pCO₂ using environmental factors and land use. Our results will provide insight into the accurate estimation of region and global carbon budget in the headwater rivers.