Abstract: The Yangtze River Delta (YRD) is the region with the highest level of economic and social development and the most active region in China. Analyses of the spatial and temporal characteristics of the carbon emissions and the associated affecting factors can provide important references for other regions of China. This study employed spatial autocorrelation analysis and standard deviation ellipse, based on nighttime lighting data from 41 cities in the YRD region from 2006 to 2021, to analyse the spatial and temporal characteristics of carbon emissions. Furthermore, this study used the geographically and temporally weighted regression (GTWR) model to empirically examine the spatial and temporal heterogeneity of the factors influencing carbon emissions in the YRD region. The findings indicated that: (1) The data demonstrated a clear upward trajectory in carbon emissions in the YRD region from 2006 to 2021, with evidence of significant spatial positive autocorrelation. The junction zone of Jiangsu, Zhejiang and Shanghai in the eastern part of the YRD exhibited a high-high agglomeration, whereas the low-low agglomeration area was predominantly situated in the western part of the YRD within Anhui Province. (2) The standard deviation ellipse results indicated that the growth of carbon emissions was more pronounced in the western part of the YRD, with a tendency for the centre of gravity of shifting towards the west. (3) Environmental regulations, greening level, R&D investment and low-carbon pilot policies exerted a negative inhibitory effect on carbon emissions, whereas population size, economic level, industrial structure and openness to the outside world exerted a positive promotional effect. Furthermore, the impact of each factor on carbon emissions in the YRD region exhibited spatial and temporal differences. These results may provide valuable references for the development of differentiated carbon emission reduction strategies in the YRD region.