The demand for temperature measurement in optoelectronic integration has prompted research on advanced luminescent materials. Here, ferroelectric Bi 4 Ti 3 O 12 :Yb 3+ /Er 3+ /Nd 3+ nanosheets were designed for optical thermometry. The transition emissions of nanosheets were significantly enhanced through electric polarization engineering. By utilizing the fluorescence intensity ratio of emissions from Nd 3+ and Er 3+ ions, the poled system achieved notable absolute and relative sensing sensitivities of 3.03 and 2.52% K −1 , respectively. These results highlight the multi-band luminescence and optoelectronic coupling characteristics of lanthanide ion-doped ferroelectric nanosheets and suggest that electric field polarization-enhanced temperature measurement can serve a reference for enhancing optical sensing capabilities.