Abstract: Highly intensive land exploitation has led to frequent reclamation and dramatic change of shoreline of a bay in China. Analyses of the evolution of shoreline and reclamation and their interaction are of great significance for sustainable development of the bay. The spatialtemporal evolution characteristics of the shoreline and sea reclamation as well as their interactions were studied taking Maluan Bay of Xiamen from 1957 to 2019 as a case. Shoreline utilization index, land use intensity index, and fractal dimension are assessed in the study. The results show that (1) the continental shoreline length decreased by 43.0% in the past 62 years, with the natural shoreline length decreasing by 83.4%. The length and of the shoreline decreased firstly and then increased generally, and the fractal dimension of shoreline fluctuated. The main shoreline type experienced a process from “natural shoreline” to “aquaculture shoreline” and then to “construction shoreline and unused shoreline”. The utilization intensity of shoreline increased from 0.27 to 0.79 showing remarkable spatial differences since 1997. (2) The total sea reclamation area was 2 187.39 hm² in 1957—2019, and the most dramatic growth was observed in 1957-1972 reaching a maximum annual increasing rate of 83.57 hm². The land use types were changed mainly from farmland to aquatic farm and then to construction land and unused land. At the same time, the land use intensity of the whole reclamation area increased from 0.25 to 0.76. (3) It can be found that both shoreline length and fractal dimension were affected by interactions of many factors such as reclamation area, coast shape and reclamation way. Meanwhile, shoreline constrained reclamation activities. Shoreline length and natural shoreline length were significantly and negatively correlated with the reclamation area, whereas continental artificial shoreline length and shoreline utilization intensity were significantly and positively correlated with the reclamation area. However, there was no significant relationship between the fractal dimension of shoreline and reclamation area. This study can serve as a reference for shoreline exploitation and reclamation management on the bay coastal area.