The Yellow River Delta National Nature Reserve (YRDNNR) is a protected area in the city of Dongying, China, which covers wetland habitats on the shore of the Bohai Sea.

In management terms, it is divided into a core area with a high level of protection, and buffer and experimental zones which allow for greater human activity.

The discovery of the Shengli Oil Field brought significant economic activity to the area, and the city of Dongying was founded in 1983.

The wetland ecosystem was degraded by the impact of economic activity within what became Dongying, as well as by inland agriculture which reduced water levels in the Yellow River.

The reserve now serves as a location for research and tourism, with one attraction being the "carpet" of red Suaeda salsa plants in autumn.

[1]: 2  The river shifted to its current course depositing silt into the Bohai Sea in 1855, having previously flowed into the ocean further south.

Local governments used the area for forestry and farming, resulting in some damage to the wetland ecosystem and an eventual loss of farmland due to land reclamation increasing soil salinity.

[5]: 17  The wetland areas extend beyond the protected reserve, and include both urban and rural inhabited and industrial spaces.

[1]: 3 [2]: 2–3  The division between the protected core area and other portions of the park partially reflects economic needs, especially regarding the oil field.

Heavy rainfall inland leads to flooding from July to October, after which the river continues a high flow rate reaching up to 10,400 cubic metres per second (370,000 cu ft/s).

Water levels remain high from December to March due to sea ice floes impeding discharge.

The river carries 1.049 billion tons of silt to the ocean each year, the highest stream load in the world averaging a concentration of 25.5 kilograms per cubic metre (43.0 lb/cu yd).

Conservation has seen populations of Suaeda salsa, Tamarix chinensis, and various reed species expand over the past few years.

[1]: 2  The Suaeda mudflats occur in intertidal and estuarine areas, and provide habitats to crabs that are eaten by birds.

[1]: 1 Low water levels in the Yellow River, exacerbated by increased farming inland, began to dry up the wetlands in the mid-1980s, although management actions since then seek to alleviate this pressure.

Dongying city supported 17 different protection and restoration efforts in the delta as of 2023, including programs to rehabilitate seagrass meadows and populations of Suaeda salsa, and to eliminate the invasive Sporobolus alterniflorus.

[8] Wetland restoration efforts begun by the Reserve Administration Bureau in 2002 have reversed the historical degradation of the area.

This has caused eutrophication in the sea water near the river mouth, the appearance of red tides, and pollutants entering the local food chain.