A variety of reptile species have been identified within the boundaries of Lyndon B. Johnson National Historical Park.  The five common turtles inventoried include the Common Snapping Turtle (Chelydra serpentina serpentina), Texas Map Turtle (Graptemys versa), Red-eared Slider (Trachemys scipta elegans), Texas Cooter (Pseudemys texana), and Guadalupe Spiny Softshell (Apalone spinifera guadalupensis).

Common snakes include the Diamondback Watersnake (Nerodia rhombifer rhombifer), Texas Brown Snake (Storeria dekayi texana), and the Texas Rat Snake (Elaphe obsoleta lindheimerii). The Green Anole (Anolis carolinensis) is a lizard that is usually seen sunning on fence lines throughout the park.

The Mediterranean Gecko (Hemidactylus turcicus) is a common exotic found inhabiting many of the structures.