Based on the enhanced charge separation efficiency of the one-dimensional structure and strong surface plasmon resonance (SPR) of gold, a gold modified TiO₂ nanotube (Au/TiO₂NTs) glucose photoelectrochemical (PEC) sensor was prepared. It could be activated by visible red light (625 nm). Under optimal conditions, the Au/TiO₂NTs sensor exhibited a good sensitivity of 170.37 μA·mM⁻¹·cm⁻² in the range of 1–90 μM (R² = 0.9993), and a detection limit of 1.3 μM (S/N = 3). Due to its high selectivity, good anti-interference ability, and long-term stability, the fabricated Au/TiO₂NTs sensor provides practical detection of glucose. It is expected to be used in the construction of non-invasive PEC biosensors.