Abstract: In flexible tunable gratings, their applications have been limited by their slow response times and high power consumption recently. In view of this situation, a near-infrared (nIR) light actuated tunable transmission optical grating based on graphene nanoplatelet (GNP)/polydimethylsiloxane (PDMS) and PDMS was proposed. By using the method of ultraviolet (UV) 1ithography, the grating structure integrating the grating with the actuating mechanism both made of soft elastomers was studied. The increase of temperature in GNP/PDMS membrane was around 120 ℃ under an actuation power density of 220 mW·cm^-2 within a period of 3 s and the grating demonstrated continuous period tunability of 2.7%. In different nIR-driven cycles, the same grating period amplitude variation was showed, which indicated that the photomechanical response of the grating was independent of both time and history.