High-temperature properties of boron nitride platelets (200–800 nm in width and 30–50 nm in thickness) were systematically evaluated through thermogravimetric analysis (TGA) in combination with differential scanning calorimetry (DSC). X-Ray Diffraction (XRD) studies confirmed the hexagonal graphitic-like structure of the material, while Fourier-Transform Infrared Spectroscopy (FT-IR) indicated the active vibration modes related to the B–N bond. The specific surface area (SSA), calculated by the multi-point Brunauer-Emmet-Teller (BET) method, was determined at ∼23 m2/g through N2 adsorption/desorption measurements at 77 K. Both high-temperature resistance and oxidation behavior were examined from room temperature (25 °C) up to ∼1300 °C under air-flow conditions. The h-BN platelets demonstrated a high thermal stability of up to ∼1000 °C, while their oxidation occurred in the temperature range between 1000 and 1200 °C, followed by the formation of boron oxide (B2O3).