Poison Springs Battleground State Park, Civil War battlefield state park near Bluff City, Arkansas, United States.

Poison Springs Battleground State Park covers about 85 acres on both sides of Arkansas Highway 76, roughly 14 miles northwest of Camden. The improved north side holds a picnic area and interpretive signs; the wider battlefield area exceeds 9,000 acres. The land is heavily wooded with pine, some oak and dogwood understory, and the cultivated ground of 1864 has since reverted to forest.

Poison Springs Battleground State Park marks the Battle of Poison Spring, fought on April 18, 1864, when Confederate troops and Choctaw Indians attacked and overcame a Union supply wagon train during the Camden Expedition. The defeat hastened the failure of that campaign, and the killing of black Union soldiers from Kansas, with no prisoners taken, brought the engagement notoriety. The site was listed on the National Register of Historic Places in 1969 and became part of the Camden Expedition Sites National Historic Landmark in 1994.

The name "Poison Springs" comes from an apocryphal tale that Confederate soldiers poisoned nearby springwater. The battle is also remembered for the killing of Black Union soldiers from Kansas, as Confederate forces took no prisoners. Interpretive signs at the picnic area on the north side of Highway 76 explain the engagement.

The park provides picnic areas, walking trails, and informational displays for exploring the grounds. The paths are designed so visitors can traverse the battlefield on foot while experiencing the natural surroundings.

The site's name comes from a story about soldiers contaminating a water source during the fighting. This account is part of local memory and remains part of how the engagement is remembered.