[Objectives] The spatiotemporal variation characteristics and driving mechanisms of ecological environment quality in Dalian City were revealed， in order to provide a scientific basis for regional ecological protection and high-quality development. [Methods] Based on the Google Earth Engine （GEE） platform， the remote sensing ecological index （RSEI） of Dalian City was constructed. The Sen-MK trend analysis was employed to reveal the spatiotemporal evolution characteristics of ecological environment quality from 2000 to 2023， and the Hurst exponent was used to predict the future short-term evolution trends of ecological environment quality. Furthermore， the optimal parameters-based geodetector was employed to identify the main driving factors and their interactions. [Results] ① From 2000 to 2023， the ecological environment quality of Dalian City showed an overall fluctuating upward trend， with significant spatial heterogeneity， showing a distribution pattern of “better in the north and worse in the south； worse in urban areas and better in suburbs”. ② The magnitude of ecological environment improvement in Dalian City during the historical period was greater than that of degradation， and the improving trend was expected to continue in the short term. However， certain local areas were at risk of trend reversal， indicating a need for strengthened ecological restoration and management. ③ The single-factor detection results showed that land use type was the dominant factor affecting ecological environment quality， followed by elevation and slope， and the driving effect of socioeconomic factors continued to increase over time. The interaction detection results showed that the interaction between land use type and annual precipitation was the strongest driving combination across all periods， revealing the ecological evolution mechanisms under the combined action of natural processes and human activities. [Conclusion] From 2000 to 2023， the ecological environment quality of Dalian City generally improved， with land use identified as the key driving factor. In the future， it is necessary to strengthen the optimization and maintain the stability of ecological patterns in urban centers and coastal areas， coordinate ecological environmental protection and restoration projects while promoting economic development， and promote the coordinated development of the regional economy and ecosystem.