In areas that are frequently affected by floods, the map showing the area and extent of inundation plays an important role in the response and mitigation of damage, and serves as a basis for planning on population distribution. settlement, economic and social development. The study has developed a method to create flood maps based on the integration of remote sensing, RTK and GIS technologies and applied it to the Tuy Hoa delta–Phu Yen province. Sentinel1 remote sensing image data from November 2021 is processed on the Google Earth Engine server, allowing quick identification of flooded areas. Combined with flood track survey data at the same time by RTK measurement technology, it helps to interpolate the flood surface model to correct the floodplain interpretation results due to the influence of buffer surface factors and terrain elevation. GIS software combines the results of flood interpretation, flood surface model and large–scale topographic map to build a map of flood area and depth. The map shows in detail 7 flood levels from 0–6 m, in which Tay Hoa district has the largest total flooded area (12.704 ha), Tuy Hoa city has the least flooded area (2.708 ha); Common flooding depth is 1–3 m (16.945 ha) distributed mainly in low–lying areas of Tay Hoa district and Dong Hoa town. The study shows the ability to integrate remote sensing images, water level monitoring systems and large–scale topographic maps for real–time flood monitoring to meet flood disaster prevention throughout the country in general and Tuy Hoa plain – Phu Yen province in particular.