Thermoluminescence (TL) of X-ray irradiated natural biotite annealed at 473, 573, 673 and 773 K were studied within 290-480 K at various linear heating rates (2, 4, 6, 8 and 10 K/s). A Computerized Glow Curve Deconvolution technique was used to study various TL parameters. Thermal quenching was found to be very high for un-annealed sample, however it decreased significantly with increase in annealing temperature. For un-annealed sample thermal quenching activation energy (W) and preexponential frequency factor (C) were found to be W= (2.71 +/- 0.05) eV and C= (2.38 +/- 0.05) x 10(12) s(-1) respectively. However for 773 K annealed sample, these parameters were found to be W= (0.63 +/- 0.03) eV, C= (1.75 +/- 0.27) x 10(14) s(-1). Due to annealing, the initially present trap level at depth 1.04 eV was vanished and a new shallow trap state was generated at depth of 0.78 eV which contributes very low thermally quenched TL signal. (C) 2014 Elsevier B.V. All rights reserved.