Abstract: Optimization of digital business environment is the key to solidifying the new development pattern and realizing the double leap of export quantity and quality. Different from the previous literature that studies the impact of business environment on manufacturing export competitiveness from a single perspective, this paper explores the impact and mechanism of digital business environment optimization on manufacturing export competitiveness by constructing a multi-dimensional digital business environment indicator system under the dual perspective of "quantity" and "quality". This paper explores the impact and mechanism of digital business environment optimization on manufacturing export competitiveness under the dual perspective of "quantity" and "quality" by constructing a multi-dimensional digital business environment indicator system. The results show that the optimization of digital business environment effectively boosts the quality competitiveness of manufacturing exports while significantly enhancing the scale competitiveness of manufacturing exports. The impact of digital business environment optimization on manufacturing export scale competitiveness and export quality competitiveness shows different effects in different dimensions such as geographic location, manufacturing R&D density and regional openness level. The optimization of the digital business environment significantly promotes the "increase in quantity and quality" of manufacturing export competitiveness through the cost-saving effect and the innovation-enhancing effect.

Key words: digital business environment, manufacturing industry, export scale competitiveness, export quality competitiveness