The vegetation of Cooper Lake State Park is dominated by post oak and various native grass species. Other tree species include winged elm, bois d' arc, Texas Sugarberry, eastern red cedar, roughleaf dogwood, eastern persimmon, American elm, honey locust, and mesquite. Most-frequently seen wildlife includes swamp rabbit, eastern cottontail, nine-banded armadillo, white-tailed deer, coyote, bobcat, waterfowl, bald eagle, beaver, raccoon, and wild hog.