Thermoelectrets of poly(acrylonitrile) have been prepared for various electric field polarization strengths. The thermally stimulated discharge current technique has been used to study the remanent charge (dipolar and/or trapped charge) stability. The measurements were carried out in a vacuum. Two overlapping peaks and a significant increase of the current at high temperature have been observed. The first peak is centered around 372 K and the second one is centered around the polarization temperature. When the polarizing field increases from 0.47 to 1.2 MV m-1 the apparent activation energy varies from 1.08 to 1.40 eV, revealing a weak polarization field strength dependence, while the relaxation time at infinite temperature τ0 decreases from 2.05 x10 –15 to 1.05 x 10-18 s. The relaxation time at 300 K increases from 3.48 x 106 to 1.7 x 109 s indicating that the trapped electric charge may be stable at room temperature for the given polarization conditions.