Taking advantage of van der Waals forces, an azobenzene-containing surfactant with a stable cis-state was designed and synthesized to fabricate photoresponsive DNA material. The reported DNA material exhibited reversible liquid crystalline-to-isotropic liquid transition under UV/Vis illuminations via the trans–cis isomerization of azobenzene. It also gained the ability to maintain the isotropic liquid state after UV light had ceased thanks to the thermodynamic stability of the cis-isomer of the azobenzene-containing surfactant. This work provides a design strategy for fabricating photoresponsive phase-change biomaterials.