Current clinical treatments including surgical resection, radiation therapy and chemotherapy for brain cancer result in high mortality due to the complex structure of the brain aggressiveness of brain cancer. Recently, non-invasive photothermal therapy (PTT) using near infrared laser irradiation has been developed as an alternative emerging therapy for brain cancer. In this paper, a biocompatible porphyrin functionalized graphene oxide (PGO) with high absorbance at 808 nm is synthesized as a photothermal platform for brain cancer therapy. Graphite oxide is exfoliated and conjugated with porphyrin through π-π interactions. This PGO is two times more stable than reduced graphene oxide (rGO) in aqueous solution. Most importantly, the efficiency of the photo-thermal conversion of PGO is increased by 89% and 33% compared to graphene oxide and rGO under 808 nm laser irradiation, causing ablation of a large number of brain cancer cells in vitro. This PGO platform containing active functional groups allows specific targeting in PTT without harming healthy cells and tissues.