Abstract: Objectives To address the pronounced heterogeneity of multi-source marine environmental data in island-reef waters, including standard nautical charts, tides, ocean currents, waves, and wind fields, in terms of spatial reference, temporal resolution, data structure, and semantic representation, a spatiotemporal environmental field construction method based on real ocean environmental data is proposed. Methods Based on static elements such as coastlines, reefs, obstacles, and water depths extracted from standard nautical charts, real ocean environmental data including tides, ocean currents, waves, and wind fields are integrated. Through coordinate unification, temporal alignment, spatial resampling, and semantic mapping, a spatiotemporal environmental field for island-reef waters is constructed under a unified spatiotemporal reference framework. On this basis, the integrated representation of static geographic constraints and dynamic marine environmental processes is realized by combining tidal-corrected dynamic water depth, wind-wave-current environmental attributes, and a dynamic navigable region generation method. Results Validation in typical island-reef waters, including the Aleutian Islands and Prince William Sound, shows that the constructed spatiotemporal environmental field can effectively represent tidal-induced variations in dynamic water depth and navigable boundaries, and can uniformly describe the spatiotemporal distribution of environmental disturbances such as ocean currents, waves, and wind fields. Further path-planning experiments in the Aleutian Islands area demonstrate that the environment-aware route generated on the basis of the spatiotemporal environmental field has better environmental adaptability than the baseline route, making better use of favorable currents while reducing cumulative energy consumption. Conclusions The proposed method realizes the unified organization and dynamic reconstruction of multi-source real ocean environmental data in island-reef waters, and can provide fundamental environmental input more consistent with real marine constraints for complex marine environment modeling and downstream tasks such as path planning.