The Leizhou Peninsula is a major grain-producing region. It contains the largest mangrove and coral reef conservation areas in mainland China, which were regarded as important milestones in coastal ecosystem conservation. However, existing studies rarely integrate socio-ecological dynamics (evolution) into ecosystem conservation assessment frameworks, and they are often conducted over specific periods rather than a continuous timescale. The regime shifts and turning points of specific indicators, as well as their interactions and drivers, have not been sufficiently investigated. Therefore, this study examined socio-ecological evolution using a combination of model estimations, site observations, and statistical records. Five decades of significant economic growth (p < 0.0001) substantially altered industrial structures, and the dominant role of primary industry was steadily substituted (with a percentage drop of up to 31.4%) by second and tertiary sectors, impacting population and employment structures. Urban industrial development created employment opportunities, encouraging resident migration from rural to urban areas as diverse employment opportunities, livelihoods, and urban-rural land-use transformation were shaped by industrial structure adjustments. Agricultural output growth was characterized by structural adjustments that transformed from an agriculture-dominated mode to a balanced development mode combining multiple industries. The prosperity of animal husbandry, forestry, and fisheries enhanced industrial and livelihood diversity, which was beneficial for ensuring livelihood stability and sustainable economy. Study findings are supposed to enrich understanding about the interplay and management of socio-ecological systems, and provide references for coastal ecosystem conservation and regionally coordinated development in China and beyond.