Graphene-based field-effect transistors (FETs) were fabricated by electron beam lithography and lift-off process and the photoresponse in the transistor was investigated. Significant photocurrents can be detected when the channel graphene near the metal contact is illuminated by a laser spot (λ = 633 nm). Both the magnitude and direction of the photocurrent can be effectively modulated by the back-gate voltage. In addition, the photocurrent will saturate by increasing the gate voltage. A maximum responsivity of 46.5 μA/W is achieved, which can be contributed to develop the novel graphene-based photodetectors.