Accurately evaluating urban built-up land green use efficiency is highly important for the full use of land resources and high-quality development. On the basis of statistical data from 2003–2020, this study explores the dynamic characteristics of urban built-up land green use efficiency dynamics in the Central Plains Urban Agglomeration (CPUA) by applying the super-slack-based data envelopment analysis (super-SBM–DEA) model and determines the influencing mechanism of urban built-up land green use efficiency via a panel regression model. The empirical results indicate the following: the average urban built-up land green use efficiency in the cities of the urban agglomeration presents a significant fluctuating trend, first increasing and then decreasing from 2003–2020. The urban built-up land green use efficiency of the CPUA is characterized by spatial imbalance. Over the studied period, urban built-up land green use efficiency has strong economic attributes and is positively promoted by economic development. In contrast, the industrial structure, environmental regulation intensity and energy consumption intensity significantly hinder urban built-up land green use efficiency. Energy consumption intensity has the strongest negative effect on urban built-up land green use efficiency. Finally, several policy recommendations are proposed for promoting urban built-up land green use efficiency on the basis of the conclusions obtained.