In this work, a series of carbon-doped Bi2MoO6 nanomaterials were synthesized by hydrothermal-calcination method using biomass carbon-glucose as carbon source for the first time. The carbon element substituted the host O2- anions in the lattice of Bi2MoO6, which induced the lattice expansion, particle size reduction, specific surface area enhancement and band structure variation. The C-doped Bi2MoO6 showed significantly enhanced and stable photocatalytic performance in removal of Rhodamine B (RhB), methyl orange (MO) and tetracycline hydrochloride (TC). Simultaneously, the carbon doped sample could also act as photosensitizer in tumor PDT and showed efficient PDT ability for HeLa cancer cells. The electron spin resonance (ESR) result confirmed that the carbon doped sample had higher reactive oxygen species (ROS) concentration than that of pristine Bi2MoO6, which are possibly responsible for the enhanced photocatalytic performance and PDT efficiency. This work would open a new window to develop bifunctional semiconductor, a photocatalyst for environmental pollution treatment and a photosensitizer for effective tumor photodynamic therapy.