[en] Herein, we present a first report on the luminescence thermometry properties of Er, Yb doped Gd₂O₂S microparticles under near infrared up-conversion excitation at 980 and 1500 nm measured in the 280–800 K interval. The thermometry properties are assessed using both cw and ns pulsed excitation as well as tuning the excitation wavelength across Yb and Er absorption profiles. For low cw (300 mW cm⁻¹) and pulsed ns (400 ÷ 550 mW cm⁻¹) excitation modes, no thermal load is observed. At room-temperature (280 K), the maximum relative sensitivity values are comparable under pulsed excitation at 980 and 1500 nm, around ∼0.01 and ∼0.008% K⁻¹, respectively. In addition, a relative intense up-conversion emission at 980 nm under excitation at 1500 nm is measured. Our findings evidence attractive up-conversion and thermometry properties Er, Yb doped Gd₂O₂S under near-infrared excitation and highlight the need to explore further these properties in the nanoparticulate regime. (paper)