Graphene oxide (GO) has many exciting advantages such as easy preparation, low toxicity, good solubility and stability in aqueous solution. However, GO itself has a low near-infrared (NIR) absorption, and thus is not suitable for photothermal therapy and photoacoustic imaging. To overcome this limitation, a novel dye-enhanced GO is prepared utilizing the π-π stacking interactions between GO and indocyanine green (ICG). The ICG-GO complex has a high optical absorbance in the NIR region and exhibits excellent photothermal properties under NIR irradiation. In order to improve the cancer-targeting activity, GO was modified with folic acid (FA). In vitro experiments showed that the ICG-GO-FA nanocomposite could be used for targeted photothermal cancer cell destruction. Moreover, the application of the ICG-GO-FA nanocomposite for photoacoustic imaging was also demonstrated.